Complete bullshit.
Opposition research into your opponent is pretty much as old as elections themself. Especially in light of most of the Trump campaign management having been convicted felons; mainly involving their contacts with Russia and having subsequently lied about it at various times. Flynn, Manafort, Sessions, etc...
Only a Trump supporter would try to raw a parallel between opposition research and paying a porn star for sex.
But that is where the Trump cult is...unhinged to the bitter end.