Waiting on J1 Waiver and i-485

[Pseudodave 0]

My wife, whom is listed as a beneficiary on my EB2-NIW and AoS and currently resides in the USA, is currently on a J1 visa with the 2 year home residency rule. 

Her J1 visa just expired yesterday and is currently in her 30 days grace period. She has hit her 5 year limit for J1 so cant extend it.

She has received a no-objection waiver from her home country (Brazil) and was sent to the U.S. State department on the 3rd of November. Current status is waiting on the US State Dept. to issue the no-objection to USCIS.

My wifes plan is to submit her i-485 as soon as she receives her no-objection. But time isnt on our side with the current backlog, unfortunately. 

My question, can my wife submit her i-485 before receiving the J1 waiver from USCIS to remain in the US legally? Then fingers crossed, have it when the RFE is extended. Or would it be a straight denial?

Is it legally possible to invoke 245(k) if she waited for her wavier out of status (less than 180 days), then applies for i-485 ASAP.

Is there another option we can pursue so she isn't forced to leave the US after her J1 grace period?

Thanks!