I485 RFE (lack of visascreen)

My I485 got a RFE last week because I did not submit my visascreen. I work as a registered nurse. My I140 has already been approved.
I have tried TSE several times. But it's too hard for me. If I didnot get a passing TSE score, I will not get visascreen before RFE deadline. And very possibly my I485 will be denied.
We concurrently filed our I140/I485 in Dec, 2004. My hu*****and is in his F1 visa. And never used his EAD based on pending I485. So my hu*****and will keep
his F1 status. Even he already filed I485.

But I am considering possible consequences after my I485 denial. If our I485 get denied, will my previously approved I140 still be valid? I can stop working immediately if I485 gets denied. But in order to keep legal nonimmigration status, can I still be F2 as before? Do I have to go out US and apply nonimmigration visa again? In the mean time, can I file a second I485? I believe for nurse, EB3 visa number should still be current within this year.

Thank you for your comment. Please no scold on nurses.