Leipzig Is not as consistent as last season but I think their chances of being in the top 4 are greater than Dortmund, currently leipzig and Dortmund are only 1 point apart and Dortmund next week will face a difficult match against Bayern Munich, so Leipzig chances of rising to rank 4 can happen if Dortmund lose from Munich, But still Leipzig should be able to get 3 points from Mainz later, In my opinion Leipzig has more chances to end the season in 4 than Dortmund.
With a record where they have always been able to be in the top 4 in the last few seasons and with points that can still catch up, it is possible for Leipzig to be able to be in the top 4 again this season, it's just that it's a little complicated now considering Dortmund is also a top 4 bundesliga subscription club besides that the increase in VFB's performance is completely out of control so the top 4 competition is still very complicated now.
Currently there are only a few matches left for the end of the bundesliga season and the advantage for Dortmund and Leipzig is that they are not too bothered because they will fight several clubs that are still below them in contrast to VFB where there are several big clubs that can make them lose momentum considering VFB's schedule for the rest of the season there are Leverkusen, Bayern and Dortmund which will complicate their steps to be in the top 4 and this can be utilized by Leizpig later.