The game currently goes off the true level of the Immortal troop when calculating Kingdom power level.
(I have another Mydnight troop at level 19 otherwise they are all 20)
Since ascension orbs and souls can’t be used to upgrade the troop the game should see Immortal troops as base level 20.
If you disagree, then it also written that these troops should start as level 15 due to my vip level.
The simplest solution would be to have the game see the troop as base level 20 like Mythic troops and therefore the VIP nor Kingdom level would be an issue.