No folks, it's always more complicated in financing than where ideas may take you.
First, let's address reality, I know that wholesalers, most being new in business and RE seek the Holy Grail of no responsibility or just being able to walk away, this is pure guru junk making the strategy seem easy and risk free.
Time is what gets you past degrees of responsibility, no contract, no disclosure, no method or no strategy covers you if you were the one that devised some plan, presented it, sold it, got others involved and it ends up being some convoluted, unorthodox, uncommon or illegal activity. Your liability goes much deeper than most newbies realize, even deeper than some of the old dogs may think who have never had some issue.
Okay, financing agreements are unilateral contracts, there is an obligation created that one party must perform. That type of contract can not be assigned by an obligated party to another without consent of the party owed that performance. Loans may not be assigned by a borrower in any instance, there is no agreement that can be made nor any disclosure or any other way to circumvent this basic legal requirement other than obtaining consent by the note holder or lender.
You can only sell what you own. If you buy Sub-2, you took a limited warranty to title and your interest is limited as your seller and the underlying lender still retain an interest until that obligation is paid off, you don't have clear title. You can sell your interest, but you can't provide good title until that under lien is cleared.
A buyer under a Sub-2 or other installment contract can sell, allow a new buyer to assume that obligation with the consent of the "lender". If you sold Sub-2 again, what you are selling is your interest, your equity, you are still obligated to provide good title and that means you will be responsible for the obligation you created until it is extinguished. You'll be in the chain of title.
The original lender could release you of your obligation, in doing so you need to ensure you don't have debt forgiven. Installment loans generally finance equity which is different than cash advanced and an installment purchased is terminated as a new installment is created. The property sold under an installment sale reverts back to the seller if that original contract is terminated and is then resold to the new buyer. The middleman in an assignment of an installment contract or seller financed note never takes title, as the transaction is not completed. This may be an issue if you are released from your obligation.
Next, it is not customary in lending to release the original borrower. While a release may be given in commercial loans, it's not common in residential even with assumable loans. Thinking you're an investor and the loan being commercial isn't at the size, scope or collateral interest of the type of commercial loans where such releases might be customary, your deal is on a residence, not a warehouse, collateral is also an aspect of loan classifications. The transaction is also involving unsophisticated parties, Harry Homeowner and Betty Buyer, are they both asset managers at their day job?
Creating an agreement to accomplish such a release will be suspect as to why the lender would release a borrower and allow an unconventional agreement that places a lender in a worse position, having two responsible parties is always better than one. Who benefits from this unconventional arrangement? You created this loan arrangement, you devised the transaction, you stepped outside the usual and customary, you created the assumption in a subsequent sale......so, no, you aren't walking away with clean hands if things go south (as they say).
Investors need to speak to their attorney and understand tortuous conduct, causing another party to become involved in something where they suffer a loss. You are responsible for what you cook up and if someone chokes on your cooking, it will be the cook who may end up suffering. You can not go out on the street and simply make contracts for anything you can dream up and get someone to agree to,
I said, basically, that time may get you past some matter. You might devise some deal where your seller is working with a new buyer for 5 years and then the deal blows up, that seller may "feel" like they agreed, they dealt with the new buyer, they had some history in the deal and they may just forget about you (their attorney might not, but they might). OTH, a deal that blows up in 2 years, that seller may not feel as obligated to you.
Time takes care of some matters as to statutes of limitations, but also be aware that some claims, such as fraud, the clock begins when the fraud is discovered not when it was committed. Straw-man deals (wholesaling) acting as a facilitator, getting in and out of some transaction that is unorthodox or not common and facilitating, what can easily be seen as financing, a matter that has many avenues to investigate to uncover some aspect that could open the door to claims of fraud. In other words, if you miss something that should be addressed or structured differently, it will be easy to color it as fraud by the omission of information or failing to address an important aspect.
Another issues is mortgage broker laws, you are in essence devising, originating and assigning a mortgage. It is different when a buyer approaches a note holder or lender about the assumption of an existing loan, it can be another thing if a borrower steps in to advise, solicit and originate deals. Being a party to the note as a borrower doesn't exempt you from such activities of conveying . State brokerage laws will vary.
Financing goes so deep that you'll never be able to contract or disclose your way out of convoluted arrangements without extensive knowledge of financing matters. I hate to kill ideas, really, investors need to try to be creative and exchange ideas, but really, financing matters really need to be kept out of strategies or at least not mix financing aspects trying to create some strategy. Stick to tried and true, conventional financing arrangements between a lender and a borrower, if you need to go further, just make a new obligation. :)