You're just assuming which what am not sure about Leverkusen where they give more priority to either the UCL or the German bundlesliga. Your conclusion I believe is based on how Bayer Leverkusen are doing far better in the UCL than they are in their domestic league but sometimes that's how things could go for a club, they may not be able to give a good and strong performance on all competitions. Basically, Leverkusen has a better chance of winning the bundesliga trophy this season than they would in the UCL, so for me, your conclusion don't hold much base in my opinion.
He has the same base that the champion teams have, Real Madrid thinks like this and if you look at Xabi, he also comes from a team like Madrid, he already has his Bundesliga, he would have won his Europa League but he couldn't, but now that he's in the UCL he doesn't want to waste his opportunity, maybe he looks after his best players or plays in a different way in the league focusing on the UCL, that's my base, because if they were putting all their energy into it, the results in the Bundeliga would be different, it is known that the UCL has a much higher level, the best players from all the leagues are there, therefore more demand, more strength, more speed, more wear and tear, but if they manage to win the UCL where technically it is possible, that prize is worth a lot to a team.
Your ideology on this sounds good but still has a much flaw from the fact that Bayern Leverkusen might have a better chance in getting the Bundesliga rather than the UCL even if they try to give their all, don't forget quality of players do play an important role and while they have excellent players there are still teams in the UCL with more excellent players. This is not like the Europa league where there were fewer top teams in comparison to them last season, this is a lot different. I still say Bayern Munich has a better chance of the UCL than them because they have been really familiar with the tournament and where still able to go far even with having a disappointing period last season.
This season Bayern Munich also can win the league if they can limits the game they surprisingly do gets defeat because often teams Bayern Leverkusen are so good that in most games in the league they can their best to savage a point even when they are having a bad game.