I've learned that the odd, non-intuitive thing about it is that the membrane blocks any herbs/spices from permeating the meat so when you cook in the crockpot adding any spices does nothing to it. You have to cook it to basically kill any bad things in it and get the membrane to a point you can peel it off and then you have to cook it to get the herbs/spices you want into it.
I'd just cook the whole thing. You'll lose some weight when it cooks and when you peel it. I have no problem eating what amounts to 2 lbs raw in 3-4 days. Slice it cross wise, that is perpendicular to the tongue, not lengthwise, the pieces would be way too long that way. I give some of the inner membrane scraps to my dog, he loves it. I just bought a 2lb buffalo tongue this weekend, I'll probably make it this week.
I posted something a few days ago in the research forum that the buffalo tongue was considered the best part of the animal.