I think that the president can establish a commission. I cannot understand why Biden hasn't already done it! It simply needs being done and presidential commissions have a pretty good record (Hoover commission was one by Harry Truman). There is now suggestions being floated about appointing 'retired' politicians to be appointed. I think the entire thing, so far, is just another political grab by one side or the other. I also think its silly.
Biden should be doing this right now. He has, in his appointments so far (he still is waiting for the congress to complete his appointments) done pretty good. Its obvious that he listens to his people and they seem competent so get on with appointing a1/6 commission and skip the congressional self embarrassment!
As a matter of fact I am going to drop a note to Biden on this one right now!