Bayern Munich will have tough matches in the Champions League and Leverkusen was eliminated in the Champions League. Bayern Munich is the one who eliminated Leverkusen. Now we can say that as long as Leverkusen does not make mistakes, there is a possibility that Bayern Munich will make mistakes after the Champions League matches. If Bayern Munich makes mistakes, Leverkusen may have hope for the championship again.
Bayer Leverkusen might have higher chances of winning the Bundesliga considering that they are out of the UCL. Since they will now focus on the League, they might be able to win more games. Bayern Munich, on the other hand still have more than one trophy to pursue which could lead to player injuries and fatigue. I heard coach Carlo Ancelotti complain that Real Madrid struggled to win the game against Villarreal because the players didn't rest after they had to play the game after 72 hours of meeting Atlético de Madrid. Except if Bayern Munich puts in more efforts they might lose the first position.
I doubt that, it would not be possible for Leverkusen to close a six point gap. Yes Bayern will get tired but I feel that 6 points wouldn't be easy at all, it requires Bayern to lose twice, which would be very tough for anyone to beat them anyways, even if Bayern is tired, they are still far greater than any team in the league except maybe Leverkusen. The luck Leverkusen had was the game between them, if Leverkusen won both, they would be tied right now.
I guess we will still have to wait and see but I do not put any trust in Leverkusen to earn 6+ more points than Bayern Munich for the remainder of the season. It is not enough for Bayern to lose six or more points, we also need Leverkusen to not lose any points, that's unlikely.