I was also strongly advised against filing for the green card without the waiver in hand by 3 different lawyers I consulted. The issue is that the USCIS manual requires the adjudicating officer to deny your case based on your 2 year rule ineligibility and not wait till you get the waiver. I even saw a case of someone who got their green card denied even though she got the waiver by the time she reached her interview stage and USCIS reasoning behind this denial is the fact that she was ineligible to apply for adjustment when she filed for adjustment. It is crazy but unfortunately that is how it is. It is a big risk . I just wish this whole nightmare process would end faster. It’s hardship on top of hardship.