Inheriting Tenants, seller evasive

[Darnicia Smith]

Hi, all. Hoping a seasoned investor can shed some wisdom.

I am under contract on a property that has an existing tenant. Seller is advising that he doesn't want to tell the tenant to vacate until 2 weeks before closing. He is claiming that he wants to ensure the sale is happening?? We literally have a contract, EMD, Title has started etc.

I have gathered that the tenant used to work for him. Has no official lease in place and pays through cash app supposedly. 

My goal was to get into this property and renovate it without hindrance. Now he is saying he would like the tenant to stay( obviously not his choice) as the tenant is paying way under market rents.  
Trying to decide if I should contact the tenant myself or walk away from the deal if he doesn't notify the tenant and have a vacate date established.