Nah, commendation should just be an extra thing that has no impact with anything and also able to vote multiple players as well to vote when players immediately leave the instance after finishing.

I don't blame a person commending someone that has a funny name, nice glam or been fun to chat with in general but the thing is connected on mentors along with some achievement rewards.
Just make it a fun experience that doesn't stress people or turn some into mindless commend beggars.

I just loathe not able to commend more than 1 person