Hi,
I think network discovery addon should be able to partially do that, no ?
But it doesn't only rely on veyon's conf.
Your master(s) should be allow to communicate with those wifi networks, which depends on your network conf (infrastructure and master's conf).
Of course, if laptops are student's personnal computer, I think it's not a good idea to ask them to setup a software on it, which gives you remote access. More than an ethical issue (already sufficient IMHO), there could be a legal problem.
Regards
E.T.