I think Bayern will be interesting to recruit Ronaldo if Lewandowski goes to Barcelona, but he is still on Allianz right now and the rumors, Barcelona can't reach a contract agreement with Bayern. So, I believe Ronaldo will not go on to Bayern for this session even though MU didn't play in the Champions League. Maybe if any other reason like incompatibility with Ten Hag style, Ronaldo will leave in half session in winter transfer I guess.
Unfortunately I see Ronaldo has started to enter Barcelona and it is not possible to accept another offer because according to him Ronaldo is a very good professional player and can have an influence on the club he works with. MU will soon transfer Ronaldo quickly so he will have time to synergize with several barcelona teams in order to get a win in this league.