I actually enjoyed the instance. It was definitely a bit frustrating and with some level of challenge but I didn't really see that as an issue given the intention of the scene. And honestly, if they're going to be doing these "play as not yourself" instances I would much rather they be like this and be an actual change to the standard gameplay formula. Rather than making me play a gimped version of a class just so I can "play as a character," give me an actual special reason for playing as that character. Give them something unique or interesting to do. Give them an entirely different gameplay experience instead of just "standard fight but with different buttons." I feel this instance completely executed in that regard.