Scarab of Neuroses

The scarab seems to be bugged; I have used this scarab twice now. Both in T16 maps. The first time I had no unique delirium bosses spawn and the second time I only had 1 spawn. I cleared the entire map both times too, so it is not possible that I missed it.

Can also confirm I've done dozens of full clear maps with the scarab, it is inconsistent, the range of bosses is between zero to both. Sad to see no updates on this, its been reported since April.