For Barcelona vs Inter game will not be that easy as Inter can be happy also with a draw in this game so that can make things pretty difficult.
I agree with you that even though Bayern Munich are playing poorly in the league, they are playing quite well in the Champions League. It is possible that they will be the first ones to qualify for the playoffs, while the second position will be decided between Barcelona and Inter Milan.
With this in mind, I would give the edge to Barcelona as they have brought in Robert Lewandowski in the last transfer window, and he has been doing what he does best, which is scoring tons of goals for them. In addition, I would like to point out that Xavi has really settled his team well and they are now playing quite consistent football in comparison with Inter Milan.
Bayern munich is a great team. When the focus of winning the Champions League is high, what should one expect from a great side as this. They would of course save their quality for injury avoidance or fatigued reasons. They have shown a decline perhaps for the absence of Lewandowski, who seemed to be a force in the squad then.
For Barcelona, I am confident Xavis team would qualify alongside Bayern, but I doubt they have the essence to out play the other teams, whose sole focus is projected toward the much coveted Champions League trophy.