Now this is an easily misunderstood suggestion....
but if you can't find ANY help, any Recycled Muso can LEARN an accordion MOSTLY by themselves, but teaching someone an instrument that you don't play yourself is probably NOT to be recommended....
The problem is that if the lad is really a talented muso-to-be, he really needs as mentors..
1) a good musician (as many as possible around him, really!)
2) a good accordeon player (as many as possible around him, really!)
3) someone (at least one, but more is better!) knowledgable in the styles he wants to play
4) Most important, given the above, someone (one is essential!) who can communicate the love of music, and inspire the student to gain the necessary technical knowledge, and practice sufficently to gain the necessary physical skills.