EU referendum, brexit and the aftermath

The DUP wouldn't support a referendum that could result in the backstop (again, as it's been hinted at). Additionally, there are the true Tory remainers. I can't imagine there are enough brexit supporting labour MPs to make up that gap. Maybe I'm wrong though.

It'd be referendum vs GE, would the DUP prefer to remain in an alliance with the government in power rather than accept the Irish sea border that would result from a Labour GE victory?

i.e. a referendum contains the possibility of no-deal, an election (if Corbyn won) would likely remove that, and any leverage the DUP had at the same time.

If the Tories won again then back to square one, of course.