Old Lion's Court CM Bosses become unkillable

[Alethia.3597]

This is on the rare scale of a bug on frequency, but when it happens you cannot complete the strike as you will end up with two shielded prototypes on the field at once.
It happens on the switch from CC puzzle to 60-20% health phase of Vermillion.   Vermillion may briefly appear, or not appear at all, then Arsenite will drop down.  Arsenite can be damaged, but when phased there will be a phase with the other two protypes both shielded.
I have seen it a few times, but only have two logs with it which shows the missing Vermillion phase.
https://dps.report/BK0h-20230209-221221_olc
https://dps.report/0027-20230315-203519_olc