Bosses Added by Scarabs aren't getting all boss modifiers

Scarabs of terrors and pandemonium both state "modifiers to the final map boss also apply to these atlas bosses"

From what I can tell they are not affected by at least:

"unique bosses are possessed" map mod
Thorough Exploration Keystone
Allflame ember of wildwood
Destructive Play
The Most Toys(and accompanying small nodes), maybe
Royal Guard