[2_listerine_pls]

He doesn't even return your calls and you are worried about coming across like an asshole? Why would He even care about deleting the data? He will tell you that it has already been erased.

I guess you could make another "startup" with fake clients and be legally prepared to screw him. Luckily, He will ask for the same info. If the fake contacts are contacted by your competitors, you can use it as proof.