it’s likely not the most cost efficient way of doing it but you could do it with HubSpot (Marketing Hub Professional or Enterprise)
you can enrich the website visitors in Clay to get the data Google needs to create the audience - likely full name, email, company name and domain. And there’s likely a min. size of the audience Google needs, which seems to be 1000 people.
then you can push every row in the Clay table to a Hubspot list. I would recommend a static list and wait for the Clay table to have at least 3000 people so you’re sure that Google will be able to match 1 out of 3 to their records and create an ads audience of at least 1000 people.
Finally you can use the Hubspot list to create a Google ads audience (Ads Audience sync feature)