P.S. It is also quite possible that the passage next to the Cavaliers is buggy; the mountains may have simply moved out of the way because of them. This is rare, but it happens. For example, recently, on a Conquest map, I had a passage directly from the starting spawn to the Treasury for this reason; see the screenshot.

This is a common bug where the rocks guarding mines, lifts, and teleporters shift.

For other guards, this bug occurs very rarely, and I don't know of any general pattern that would allow me to explain or identify it.

In particular, this is clearly not the case here, simply because there are other objects between the Cavaliers and the potentially shifted rocks.

Added 1 minute ago

So, is it still a single passage with a doubled (and shifted) guard, or are there 2 separate entrances to the Treasury?

Judging by the picture, the latter.

But if I were in the AK's position, I wouldn't accept an appeal for such an episode.