I assume that you want to use some kind of middleman,who will run the Google/Bing Ads accounts for you.
Using a middle man increases the risk of being scammed.You must seek for someone extremely trusted and reputable.
I'm confused.Why can't you just sell your crypto for fiat,get a debit card and use it to buy Google Ads?
Is this so difficult for you?
Starting from scratch takes time and lots of trial and error to setup campaigns and manage. I've been there.
Or he could have been banned on the platform and needs a third-party to do so.