Richard & Paul, not necessarily dry clean and you shouldn't be afraid of them

Marcus hasn't even said if it is a velour or flat weave, yet you've just gone and put the sh*ts up him for no reason!!
Richard, if you'd have wet cleaned that seat cushion and re-set the pile by grooming it afterwards you might have walked away a hero

Most modern viscose velour fabrics can be cleaned with a wet system
after thoroughly testing somewhere out of sight which includes wetting up, checking colour loss and then drying off completely to check for texture change.
Older ones aren't always a no-go either but more risk with them than modern viscose. I managed to do a low moisture clean on a viscose velour that was from the 70s with a pile height roughly 10mm... When quoting, I told the guy how bad it was going to look if I wetted it, wetted up a hidden area and walked away and left it with him. He phoned me back to book the job in after a few days, said it was fine, I was gobsmacked!
I have encountered a few viscose velours that had a kind of mottled effect... when wetted and dried out they lost the mottled appearance and went ever so smooth and shiny - a definite dry clean only, unless the customer instructs you otherwise after being made fully aware of the situation (and then you have to make sure the cleaning is dead even all over!).
Show it fear and it will bite you. Show it who's boss and you'll walk away with a customer for life.