Abyss Spire in Canyon can spawn portals under terrain which never close

Bug Report ID: #4181862609
Bug Report ID: #3643279713

Running Abyss on Canyon, some spires will spawn an abyss portal underneath terrain like rocks or cliffs. If a portal spawns there it will never close.

Might be related to a check regarding the hoards scarab that a hoard can not spawn under terrain, because I haven't seen that behaviour before otherwise.