For a brief moment I thought they had some significant backing as the had UNESCO, WHS, Ramsar, ICOMOS, Global Heritage Fund etc logos at the bottom of their webpage
But it turns out this couple are just "Supporters of" those organisations.
Els maybe you can bring back your photo of that handpainted WHS logo from Ethiopia, and just say you are a supporter!
It looks like a very swish website, and fair play to them for choosing such an enjoyable hobby, though I think they will end up a fairway short of their goal. They travel to about the same number of sites per year as me (pre pandemic) and if I ever get over 33% I would consider that an impressive feat.