When the Hungarian ballroom world champion comes to the US to teach dance to wealthy students, he quickly discovers the corruption and betrayal that stand between him and the fast-fading American Dream.

You need a face to the bad guy.

In order to better visualize the dance instructor, it might help to add an adjective or two (like naive, ambitious, impoverished, etc). The corruption/betrayal angle is intriguing, but a bit generic. Maybe something more specific (like a student who accuses him of sexual abuse in order to attract the attention of someone else that leads to instructor going to jail/bankrupting him. Maybe a male student accuses him and the instructor is homophobic).

Very cool, but what does the protag do with the “discovery?”

Example:
Immigrating to the US to teach dance to wealthy students, a famous Hungarian ballroom instructor must overcome the corruption and betrayal between him and the fast-fading American Dream.

Keep going!