It's interesting how often this actually happens, and how frequently there are very real consequences for the developers. It sort of reminds me of how Tango was forced to use Id Tech 5 for The Evil Within; an engine first not suited to their needs, lacking probably the requisite support of a more established engine, and in fact counter to their needs in some respects (no dynamic lighting, something they ended up building themselves which in turn tanked their FR, and so on and so forth).
I understand *why* it happens. You blow money on acquiring some team, get their technology in the deal, and then feel compelled to use that same technology -- or you spend a bunch of time creating internal tech and want a one-size fits-all approach; but to actually get your engine technology to a point where you can reasonably say it's "ready" to fit all game needs, I mean, that's a dark road of denial for most if not all tech houses if your name isn't Epic.