If you still have a copy of the ScubaProf spam then please forward it to
abuse@domainsbyproxy.com. Add a line to explain that this domain has spammed you and that your email address was taken from a hacked site, namely RBW.
This will be forwarded to their webhost, godaddy.com who should bin scubaprof according to their T&C's.
That's all you need to do.
If you're wondering whether you can be bothered, just consider that someone I am assuming is not Cedric Verdier is posting as him and about his 240m dive on that site.