Derelict Mansion boss keeps dancing

The boss does not start. This is the second time this happened and very very annoying. Please fix this

report reference number: 3699911502

The only way I've found to avoid this from happening is to not get close to the boss room while doing the rest of the map. I think there's an error of some kind with the area that triggers the fight to start - both times this happened to me I got close enough to watch the dancing and there was a frame skip, then when I tried to start the fight it was busted. If I didn't get close it wouldn't happen.