Have you considered coinfections with other critters besides flukes? The gas reminds me of giardia, and albendazole, although not commonly prescribed is active against giardia (if I remember right about 5 days of albendazole).
Mattk3's protocol for flukes is combined Praziquantel and Albendazole taken with dairy calcium (yogurt, etc) and Vitamin D3 (the supplements supposedly help the medicine penetrate the flukes better. I've been taking the combination continuously for nearly 50 days and it's been more effective than the 10-21 day treatments of ALB + PRZ with 7-day breaks (I did that for 6 months and simply went around in circles). My flukes have been in the liver as well which is more complicated than if they are simply in the intestine.
I've also done some Ivermectin every so often. And I've been doing baking soda enemas as well to help clear out dead matter and egg masses. I've done some niclosamide at times as well and it seems to help, but I also have Tapeworms and some others so I'm not sure what it's done for flukes. My niclosamide is mixed with a laxative and I've even wondered if it wasn't simply the laxative that was helping.
You might also search some of Mattk3's more recent posts regarding larger flukes... seems like there is a combination involving Levamisole.
Hopefully, what you are doing is continuing to work and you don't need anything else... but thought I'd chime in.