Fan switch not working ever since my husband fell against the wall/switches- should I replace the 3 gang box?
It's highly unlikely that the box itself is broken and causing this problem.

What you should do next is remove everything from the box (label the wires first). Also remove each wire nut and put it back on, one at a time. In doing this, you may find a loose connection or wire nut. If not, then inspect each wire to make sure the plastic covering is intact. If you find anything broken, you might be able to shorten the wire past the break. Now put everything back together.

If it still doesn't work, it's time to call a professional.