Without exposing myself to TOO much criticism, yep - game meat affects me the same way!
Although I've gone through a ton of "animal" nutrition and "digestive biology," this topic was one that came up with a doctor friend of mine. In a nutshell, what he said was this: Everyone's body "handles" the digestion of "food stuffs" differently; although all humans go through the same general process, we all have our unique blend of "gut" bacteria, enzymes, etc. and break down - and process - different things a little differently than others.
Some people internally process Sulfur, Methane, and other nutrients and by-products of digestion in a manner that doesn't "break them down" the way others do, and send those gases right on through, rather than "bundling" them shall-we-say.
Protein foods are the worst offenders (no pun intended). Depending on the TYPE of protein, some causes more affects than others; i.e. beef vs. elk/game vs. chicken vs fish, etc... OR... whey protein vs. other proteins. ...Wilderness Athlete Bars are AWESOME and I use them extensively each season, but the protein they use ends up creating a "hostile work environment" for the folks that I hunt with!!!!
Other protein bars (with different protein) don't - or not as much.
...and dehydration only serves to exacerbate the situation! If you're the type of person with this "situation," FLOOD yourself with fluids before, during, and after eating (water - NOT beer!!! ...that'll only make it worse!!), and it'll greatly reduce the "issue." Also - BEANO and other things that are supposed to help with those things DO help a little for me, but - not everyone.
Funny topic - but one I used to use as a way to "prove" my opinions regarding scent-control clothing!!! LOL!!!
Chris Roe