I am assuming you are an astute investor and that there is an inherent value in purchasing a junior lien that far outweighs any off-setting risks.
Since they are both owned by the same lender, why not pursue the senior lien and offer to purchase their non-performing 1st at a discount? This is the avenue I would explore unless there is considerable equity by purchasing the 2nd.
As the new owner on the property (if you do purchase the property at auction), you have the ability to bring the 1st current, acquire the first at a discount, work a short sale on the first, and/or bring all your relatives to the property, hold hands so that the property is surounded by all of you and then do a "home-buying chant" to dispel the eveil lender spirits.
Actually, doing a short would be a new idea to me as you are now technically the owner on record and it may be an uphill battle with teh asset manager/loss mitigator as their premise is that they won't allow a short sale on your own property. uHum...
Keep us posted. I'd like to hear what you choose.