I don't think Borrussia Dortmund will be able to stop Bayer Leverkusen this season because Borrussia Dortmund will have to fight again to get into the top four of the Bundesliga standings. But for Bayern Munich, it is still quite possible for them to stop Bayer Leverkusen because considering that the distance between Bayern Munich's points is still quite close to Bayer Leverkusen in the standings, it does not rule out the possibility of making Xabi Alonso's team difficult again in the second half of this season.
The two have met but the match ended in a 1-1 draw, the opportunity to stop Leverkusen is impossible because Dortmund is fifth in the standings now. Leverkusen was even able to draw when facing Bayern Munich, which is much stronger than Dortmund. This season the Bundesliga is a little different from previous seasons because the dominance of Bayern Munich and Dortmund will be broken again if Leverkusen manages to appear solid until the season ends.
Xabi Alonso just needs to do something so that his team can be much more solid and consistent and maybe he needs to pay attention to player fatigue when playing. If this can be handled well then Leverkusen has a real chance of becoming the team that will lift the Bundesliga trophy this season.