Well, after going to 2.40 and flashing the official 3.35, i'm in business! After talking to a Sprint Rep i played dumb on the ESN and said the guy i bought it from said the phone was fine, he put me on hold, and didn't give me an explanation.. just simply said "Well, i got it taken care of for you. I had to put in a ticket for it, but we'll get back to you in 24-48 hours and get you the programming info." Sure enough, the next day i got a call from a different rep who helped me with the ESN Swap and Programming.
It worked! My bill is exactly the same as it was and everything is kosher.
I just wish i knew what the guy did so we'd know what to hassle the Reps for.