odds are that the FHG is dynamically created and this is why the 301 code comes up when submitting it to script based TGP sites.

FHGs are NOT meant for affiliates to submit to TGP sites, instead, they are meant for TGP site owners to use to fill out their sites and get credit for their traffic. If you want to submit galleries, you either have to make them yourself or speak with the affiliate rep for the company you are promoting and see if they will host them for you as plain html.