honestly vash relies on luck and playing dirty too (and talking his way out of problems) so it definitely might've been similar situations they helped one another out in! i love it being a friendly relationship, they seem like types that would get along well together and probably get into a bunch of trouble and fun. vash gets along really well with droids (just like he gets along really well with everyone), so while he wouldn't disapprove of the shadiness aspect i think he'd be pretty concerned on behalf of any a.i. (he's also close with ~snarkbot down below). he knows some people gotta do what they gotta do to survive though, so he wouldn't write the guy off and wouldn't scold him, just might redirect any droids he knows! or to keep the potential cat and mouse between him and snarkbot secret to start vash could not know about that aspect at all.