What you were expecting to happen, and what actually happened:
Should have upgraded to power level 3 even though I have satisfied all requirements, but it says I have only one epic troop. I have 2
It’s only clear if you know there are later requirements that say “Ascend x troops to mythic”.
Generally if the game says “collect x epic troops” it means base rarity. The hint is you can’t “collect” an ascended troop. You “collect” it from opening chests. If the game wants you to ascend the troop it says “Ascend x troops to .”