Of course, no one can be 100% positive that clients/escorts have tested negative or are on PrEP or have not fucked since they have tested negative. And even if they have PrEP is not 100% sure to prevent infection, just as condoms are not. For me, I find out the meaningful facts as best I can, speak with the companion to see if I can sense whether I can trust him or not and then decide whether the risk is worth it IN THAT SITUATION. If that is not for you, then decide the circumstances that you are comfortable with.