Pending H4 status in the country

Hello Everyone

I am going to mention my friends case here since he is in some trouble. He is currently on H1B from Employer A and he married his wife who had apparently come to US on tourist visa. His wife current status in this country is “Change of Status from B1 to H4”.

Now my friend got another offer from employer B who are willing to offer him this job incase he transfers his H1 to employer B. With no premium available, he will have to wait a long time until his H1B with employer B will be approved.

Meanwhile since his wife’s H4 is still not approved, his employer A has to not revoke his petition so that his wife’s petition for change of status is still active. My friend is thinking to get his H1B approved from employer B and then ask his wife (whose petition is highly unlikely to get approved) to get visa stamping done sometime in march 2019 with Employer B approved H1B petition.

  1. Now for her H4 stamping, can they ask his wife for his husband’s latest paystubs with employer A since she has been in US based on her pending status with her husbands employer A petition?

  2. Should he wait for his wife’s transfer of status to H4 to be approved before she steps out of the country?

I know this is a bit complicated but just wondering what all things his wife should carry for H4 visa stamping?

Thanks in advance.