I strongly suggest applying for I-131 and I-765 while they're free. You can relay the message to him.
I-131 - does she have any family left back in home country? Imagine if somebody gets seriously ill or dies. Or some other emergency happens. She wouldn't be able to leave without this else she'll abandon AOS process.
I-765 - Even though she may not work now, what if she decides to do 2-4 hours of work per week for socializing at a local coffee shop?
Additionally, EAD may be needed at DMV to get driver's license or state ID (please don't tell me she doesn't need it). Also, to open a bank account, or add her to his accounts, she may need to show EAD.
TLDR: there's no reason not to file these forms, since they're free right now. Tell your friend not to limit his wife's freedoms, she already goes through AOS and immigration which have a lot of restrictions.