This really sucks for you Mellisa and BG isn't defending the guy who sold it to you...BUT....you did know it had one eye when you bought it. BG isn't sure what the guy told you, but you could assume that it may have some problems.
BG isn't sure why you would do this trade, but you did. This animal looks like it's gonna need a leeetle extra care to keep him alive. If you go to the BOI like people suggest, you'll probably leave with a bigger headache than you already have(BG agrees with Smitty here)...especially with this deal considering you knew it had problems to begin with and it has now been a month.(why did you wait so long?)
You can try and assist feed him for a while and hopefully he'll figure out how to eat on his own.
Oh yeah. If you are trying to feed them together you are asking for trouble....and a possible injury which will surely be brought up on the BOI. BG doesn't care how it was housed before. It's not a good idea.