Just watching? I thought cuckolding is a young man having sex with the wife while the husband is masturbating while watching. Then the young man orgasms in her and the husband then has to lick/clean up her pussy?
Cuckolding is when a man watches his wife or serious romantic partner have sex with another man, or more loosely, some people even use it if the husband/male partner is not watching but simply turned on by such fantasies or the knowledge that the wife/female partner is having sex with someone else. The "bull" may often be a larger, hotter and/or younger man, but these are not requirements. Masturbating, "cream pie" by the other man and cum licking are definitely not requirements for cuckolding, (although I'm sure some people are into that and you might see it in some cuckolding porn). "Cuckold" historically referred simply to a husband with an adulterous wife. Over the past 20 years the term has also been widely used to describe the sexual fetish where a man is turned on by his committed partner choosing to have sex with someone else.
So you can't truly have an SP with a "cuckold" client, since the SP is not his serious romantic partner, but he could have a cuckold role-playing fantasy with her and another man. I don't think it's totally wrong to describe it as cuckolding; something like "cuckolding role-playing" might be more accurate but it's really semantics. In answer to the OP's question, no, not personally.