Originally Posted by Demise

Having worked on cases like that (hardship to parents) it's definitely doable. As long as they're kinda old and have any medical or psychological issues you can definitely get approved. People have this weird notion that your relative will literally die without you to get a waiver approved and that's not true.

For the most part, USCIS doesn't care at all how you're seeking a green card (DV Lottery, I-130, I-140, I-360, I-526, as the principal or a derivative), they only require you to have an approved and current visa petition when you file I-601A.

I have previously worked at a law office and we did quite a few combinations of I-601As.

1. Multiple IR with qualifying relative being the petitioning spouse (USC).
2. F-1 with qualifying relative being the petitioning parent (USC).
3. F-4 with qualifying relative being the mother of applicant (LPR)
4. EB-3 with qualifying relatives being both parents (LPR), in this case we actually had them petitioned by the applicant's USC sister while we were doing his I-140.

We also had a few I-601s for other reasons:
CIMT waiver connected to a I-526 petition and adjustment of status, qualifying relatives were the principal spouse (LPR) and daughter (LPR)
CIMT waiver for a returning resident before an immigration court, qualifying relatives being both parents (LPR)
Misrepresentation waiver connected to I-130 by daughter and AOS, qualifying relative being the spouse (LPR)
I-612 foreign residency requirement waiver connected to I-130 by the spouse, the qualifying relatives were the spouse (USC) and son (USC)


Honestly, unless your relative never had a complaint in their life you can always find something to use. There's a few things to consider:
1. The "extreme hardship" standard isn't insurmountable.
2. You control the narrative, you chose what parts to focus on, you chose which parts to avoid. Yeah you might get an RFE to prove your assertions a bit further but that's kinda it.
3. The standard for evidence is "preponderance of evidence" or in simple English - more likely than not.

tl;dr - He'll be fine.