I have been in the really high level SEO space for a long time and the second I saw this it made me very uncomfortable for that reason.
Theoretically it absolutely could, in reality, it's hard to say but I wouldn't be overly enthused about people pointing random domains at any site I owned.
In short, Not to trash the people behind it, it is really well intentioned and I love the concept but reality may pose problems that end up doing more harm than good.
To the causes, the referring traffic source likes like it's coming from Domains4Good.org.
A cause would only seeing referring traffic when it's promoted as the top cause of the day. Links onsite at Domains4Good from cause submissions would also ultimately add to SEO value. Social referring traffic through Domains4Good promotions across all channels, not just redirect, will add value as well.
Theoretically it absolutely could, in reality, it's hard to say but I wouldn't be overly enthused about people pointing random domains at any site I owned.
In short, Not to trash the people behind it, it is really well intentioned and I love the concept but reality may pose problems that end up doing more harm than good.