Ok. Did test in guild hall on Vlar. 0 buffs or Auras. I also removed the worn2 spell damage items Lucid Twilight Shroud and Aged Emerald Adorned Brood Ring. I also removed Totem of Pure Energy to remove any chance at twin cast. She has donor fire focus and dark versions of all other focus effects and Faerune 3 worn.
Without BP click:
Complete Destruction - 27103 x1, 129312 crit x1
Chaotic Detonation - 29,452 x 4, 95950 critical blast x 2
Zero twin casts as there shouldn't have been without Totem
With BP click:
Complete Destruction - 107,290, 33104 crit x 1
Chaotic Detonation - 79452 twin cast x 5, 97718 crit combined with a 79452 X 1
It didn't twin cast Complete Destruction which I think it did used to. It did twin cast Chaotic as intended. The damage did increase with no buffs
With equipment re-equipped nothing changed other than the 15% increase that I should have gotten from those 2 items.
With buffs from Sune donor arms, Auras of the Bloodmage and Warbringer, donor weapon 2.0 familar:
Without BP:
Complete Destruction - 141025 crit x 1, 29350 x 1
Chaotic Detonation - 103809 crit x 5, 30785
With BP:
Complete Destruction - 146625 crit x 2
Chaotic detonation - 104809 crit + 81785 x 5 all twin cast, 81785 twin cast X1
So I was mistaken about the twin casts as that does seem to be functioning as intended. The damage did not change much with buffs and BP going vs no BP click. It also does not look to affect the 2.0 epic click in any shape or form.