The majority can be but arciela on wave 3 was an instant loss before reisen gears, not sure about now as I havent tried since, but her meva was too much to overcome within the time limit. Also, teodor isnt a deal breaker with trusts but without, he might slow you down so much it may result in a fail, would be curious to see though for sure.
Her resistance change based on the hand glow but she still takes reduced magic dmg, so its slower. Also why are we discussing solo without trust? Who cares at this point... its a viable method to farm gear from an event that is still relevant.