Kompany has not fulfilled his promise to win a trophy for Bayern Munich because the season is not over yet and it is not certain whether Bayern will win the title, moreover the points difference with Leverkusen is only 6 points not 11 points so there is still hope for Leverkusen to catch up with Bayern Munich and in their meeting later it might show a fierce competition and Bayern Munich must not lose if they do not want to close the gap, as said by @Altryst a draw is enough for Bayern in the match.
I cannot remember Kompany promising the club that he would win the league title with Bayern Munich on his debut as head of managers, If I'm not mistaken, Kompany was appointed to improve the team's performance; despite the fact that many people rejected him from the beginning of his time as Bayern Munich manager, saying that he could not put Bayern Munich in a better position, and Bayern Munich may lose their chances of finishing in the top four this season.
You are right. Kompany did not promise to make Bayern Munich get the title; I did not see that anywhere, so I’m surprised seeing him say Kompany has not fulfilled his promise. However, nobody even expected Kompany to be good at managing Bayern Munich to this extent.
Let’s be honest: with the way everybody was criticising Bayern Munich management for signing Kompany as their manager that time, no one expected him to be this good, and unfortunately, Kompany surprised us. As it is now, Kompany has the highest chance of getting the Bundesliga title this season.
However, with the distance between Leverkusen and Bayern Munich, even a draw against any opponent is not enough for Bayern Munich, they have to make every effort to defeat every opponent they face. However, a draw against Leverkusen will be enough for Bayern Munich because Leverkusen is the only team that has been able to make it difficult for Bayern Munich to win the league title since the previous season.
Although I understand that Bayern Munich needs to work harder to be able to secure their top spot more, still, if you look at it now, they are still far from Bayer Leverkusen. They are ahead of Bayer Leverkusen with 6 points, which is still far, although I understand that Bayern Munich should put in more effort, and they are also not showing any sign of weakness. Bayern Munich is still okay.