Delirium Scarab of Neuroses possible bug?

I have found that sometimes with the Neuroses Delirium Scarab, not all of the Delirium bosses end up spawning in my map. I'd say about half of the spawn in both Krosis and Omniphobia, but alot of the time it's just omniphobia, Sometimes 2 Omniphobia's and No Krosis or Vice Versa. Might be something worth looking into