In most of the cannibalism cases I've heard of, the animals were being fed enough. They just did it anyways. The owner usually comments on how it was being fed properly and how they had always gotten along up until then.
There's a lot of other reasons not to house them together though - stress, disease spreading, and health monitoring come to mind. If one has a bad bm or you find a regurgitated rodent, how will you be able to know which one isn't doing well? Also I hear "cuddling together" is often their subtle way of fighting for dominance over the best hide/basking spot etc. etc. etc. Being cold-blooded, they can't "huddle together for warmth" like a lot of people think. They're just curled up together there because that was the most comfortable place to be temp/security wise, the fact that it was already inhabitated by another snake was probably stressful for them if anything.
Hoggies are solitary animals in the wild, they usually only come together during the breeding season. I don't think it's best to house them together otherwise. A lot of people say they've done it for years without problems, but that's like saying you've (dumb random example) smoked for years without any health problems.
Yet. There's a few well-known and accepted cons/risks, but I can't think of a single pro for the animal... I don't think it's worth it. I would suggest you seperate them just to be safe. It's better than "sorry" and all that. Two tanks half that size would still work for your display.
It is a
very nice display you have going on by the way, with simply adorable lil' hoggies!
I'd just suggest that you add more cover and hiding places for them though~