Like many here, I second the speculation of Escape being Hiromu's mother. I mean, Remember how Ryuuji wondered why Jin looked like the way he did back when Ryuuji was still just a high school student? The fact that Ryuuji is the oldest member on the core three Busters means Messiah must have used the image of Hiromu's mom in her younger years to create Escape.
As for Enter, there is a possibility that it could be someone else in the Scientific team that Messiah made an avatar of. Someone that Kurorin knows well, but doesn't recognize in the present form as Enter.
I'm more interested though in what Jin intended to do with the Enetron he'd been jacking? I mean...it could be an obvious answer, but I think there might be a possibility he's spearheading a coup along with scientists that may not be under Messiah's control. Sure there's the issue of the suffocating atmosphere in hyperspace that makes such an attempt difficult, if not impossible, but still...I think that's what might be going on, especially after Jin declared that his Enetron had been taken away after barging into the base.