@lastnightidreamtofpotatoes - personally, I'd suggest that he puts that in his statement, mentioning that he's helping support his family, highlighting the skills that he's gained and their applicability. So basically, flag it up as a positive.
Unfortunately, the metrics are quite crude when it comes to capturing background, as op has said, so he's unlikely to get a contextual offer based on what you've said. The only possibility would be for his school to bring it up directly, which sometimes works - at least, based on where I've been Admissions. When I was at Oxbridge, I'd get a number of heads ringing me every year about students, less but still a fair few in the RG and in post 92, there were three altogether - so it often depends on the stakes, and how much the school is willing to use their capital to intervene.
@LoniceraJaponica, post 92 tend to do the more applied type of subjects your daughter is looking at very well. As well as the overall results, look especially at staff-student ratio (you want this to be low) and the employment rate on graduation for the course - even better if it's divided into work types, so you can see whose degree is getting them into relevant jobs (otherwise, it could just be students who have made their part time retail jobs full time - which is great for them, but too many of these indicates a lack of immediate employability)