protein farts are REAL. Your gut bacteria are fermenting all that chicken and beef into pure sulfur gas, and the onions in your dinner are just making it worse.
Honestly the main issue is your diet is protein + rice + fruit with basically zero veggies. Your gut has nothing to work with besides undigested protein so it just produces straight death gas. Throw some spinach or broccoli into your lunch and dinner, barely any cals and it'll help a ton.
Other than that I'd add psyllium husk on top of your Benefiber since it's a different type of fiber and helps move everything through faster. Grab some digestive enzymes to take with your protein meals so it actually gets broken down before bacteria can feast on it. A solid probiotic helps too since the good bacteria crowd out the sulfur-producing ones. And this one sounds weird but chlorophyll tablets legit neutralize the smell, worth a shot.
Also cut back on the onions or swap them out, those things are sulfur bombs.
Add some greens, stack those supps, and you'll stop clearing rooms. Good luck with the surgery prep man, give that a whirl and report back!