I look for the single room bathrooms at work. Generally i can reach from the toilet to the sink to rinse...
If that's not an option, I wash my hands before entering the stall and soak the paper towels... Remove cup, reinsert and then wipe any mess off my hands with the wet paper towels. I put that in the little sanitary trash can in each stall so I don't have to walk out with bloody paper towels.
Sex toy cleaner works too as a cleaner. Or just plain soap and water! Boiling is going to lessen the lifespan. Vaginas are not sterile environments and do not require products to be sterile...