Assuming your LG is primary petitioner with H1 and you are H4. He filed GC sponsored by employer. The crucial to his status is to keep alive beyond 180 days.
1) If he maintains longer than 180 days with H1, when get laid off, he can just transfer to another company with H1 and you still maintain H4. Well, after 180 days, he can also use EAD and find another company. The old employer cannot revoke his GC.
2)very risky to use EAD within 180 days if he get laid off. Both of you will lose status and have to leave US.
well, no harm to apply EAD but only use after 180 days to switch company.There are still other risks of 485 denial by other incomplete documents or failure to response.