That doesn't remotely come close to passing the sniff test.
First, that info came from a recruiter. He probably wasn't lying; he probably just doesn't know how medical GME obligations work. It's a complicated system - read some of the threads here and you'll see some occasional debate and confusion, even between those of who are military doctors who've lived the ADSO thing. There's probably one medial corps accession per 50 or 100 recruiters out there. The vast, vast majority of them simply don't deal with us enough to pass a threshold level of competence. We are different than enlisted and the officer line.
Second, civilian deferred residencies don't incur additional obligation. That bit of info is just wrong.
Third, I'm about 99.2% certain that all military inservice residencies always incur 1:1 obligation (to be served concurrently with the ADSO from HPSP or USUHS) no matter what path you took to get there. Because once you're in the medical corps and in uniform, you look just like the guy next to you. There's no special 2-year-HPSP exemption that I've ever heard of. And I think I'd have heard of it if such a beast existed.
I've never done the math rigorously, but a 2 year HPSP probably doesn't make financial sense even if you go GMO & out - you'll still have loans from 1/2 of med school, and those will compound during your GMO days.