I'm not sure, IMO the primary applicant's status has to be in h1. Just a guess, otherwise even if she applies for visa what will be the start date in her passport, she cant be in  h4 from the second week of september, since ur frined is not on h1 tilll oct 1st.
I could be wrong though. You can ask your friends spouse to call US embassy at nepal and inqure more.

Good luck!!