Even if ASL is accepted as a "foreign" language, I doubt that any school can be forced to teach it as such. As it is, no college offers every possible language. They don't even offer all the more "common" languages. I don't think a lawyer can force a college to determine course offerings and requirements.
If you can find out the procedure for requesting new course offerings, and follow that procedure, you might have a chance. I have a hearing friend who is doing that now. She wants to introduce ASL courses at a local college, so she has tackled the process, which requires research, petitions, etc.
