Topology that makes polyanya loop

[Will-Carson]

I've managed to create a mesh with a topology that causes polyanya to keep looping without ever finding a valid path. Despite the relatively low poly count, polyanya will get stuck trying to generate medium length paths that go from one plateau to another. Occasionally it gets stuck on the same plateau, despite the plateau's having really simple geometry.

While plateau -> plateau paths almost always fail (i.e., it can't find a path up the stairs), I can often generate 3 shorter valid paths: Some point on the plateau to the base of the stairs, the base of the stairs to the top of the stairs, the top of the stairs to some other area on the plateau are all valid paths. However, the starting point on the first plateau to the end point on the second plateau is NOT a valid path. This means

A->B, B->C, C->D is valid but
A->D is NOT valid.

That seems strange. I believe this reflects some internal bug in polyanya, or if not and I'm just doing something wrong maybe that could be better signposted.

Reproduction: https://github.com/Will-Carson/polyanya_repro