Spanish doctors don't really get busted by the authorities there because no political will exists to bust their national sporting heroes who are doping, Davis Cup winners all. What happened after the Fuentes scandal? Nothing much. No national enquiry that I know of. Nor any general consensus for a clean up. The Spanish government even released a statement at one point denying the involvement of any tennis player in the Fuentes investigation. That was a straight political choice, not to investigate. Dr Fuentes had made it clear himself that he was involved with tennis pros too. His claim, that he could have got the Spanish 2010 World Cup victory rescinded, speaks for itself and was never taken further either.
Doping has long gone on in tennis. McEnroe probably doped, particularly in late career when his estranged wife made claims relating to his steroid abuse. He also infers use of recreational drugs in his auobiography - something I've come to recognise as a good sign that something else more serious is going on in parallel. Sampras is rumoured to have blood-doped, to address his inherited blood disorder. Agassi doped after teaming up with his trainer, Gil Reyes. Tennis players simply don't bench press 350 pounds or so. His admission to crystal meth use, again a digression, wasn't one tenth of the whole story. Rusedski and others may have doped, well after the ATP had told players to stop using its contaminated supplements (some with nandrolone to assist recovery). He got off on a technicality, convenient to all including the tennis authorities although there is now doubt that the nandrolone level tested for was fair as it is also endogenous. In those days it was the ATP/WTA themselves that did the anti-doping, a complete joke.
It's little better now. The ITF budget is miniscule in relation to what is really required. There's a head in the sand attitude generally about doping in tennis, with an adoring public more than ready to accept the fairytale fantasy that tennis is a drug free sport and a less-than-inquisitive reporting press. The one difference I see with with cycling is that doping in tennis isn't as conspiratorial and cannot be as organised as it is in pro-cycling. Players tend to maintain their professional distance from one another and by and large keep their doping secrets guarded. The doping doctors, as far as we know, are principally associated with other sports, hence what we see now with del Moral.