I think this advice is severely, maybe even dangerously lacking.

What LW needs is at least one adult in their corner before they say anything to these kids. Ideally parents, but hopefully someone else with some power. Because if the parents they babysit for are indeed homophobes there may be no limit to their retaliation -- firing the LW could just be the start.

I think the columnist is encouraging this kid to write a check they may not be able to cash, which could have massive consequences. Doing the right thing often has a cost, and the columnist only began to touch on that in their reply.