Default [Q] Htc desire hd or inspire 4g? Think I have been cheated.

I bought HTC Dhd from eBay and when I search on imei checking websites they tell me imei belongs to HTC inspire 4g.There is no at&t logo at the back, but changing the outer cover is no big deal.Before blaming the seller, I just wanted to get confirmed.I currently live in India and 3g works on 2100mhz here, inspire 4g doesn't support 2100mhz but HTC desire HD does.I am NOT getting any signal when I switch to 3g mode.What do you think.Any other way to get confirmed?Thanks for your time..