Access to search console?

I've got a client that wants me to take over their website and seo. I've asked for access to their search console, GMB and analyitics. However the client said they didn't know what the details and instead asked the previous agency for the details.

The client sent a copy of the message he got back and it basically said he doesn't have any Google accounts and if they want to give someone access to search console they can add the person.

Now to me that sounds like bullshit. The client had been using the previous agency for 2 years and realised they didn't know what they were doing before deciding to cut ties. The hosting of the site is with the agency, and from the messages I've seen, it seems they have complete control of search console, GMB and analytics.

How can I take control of search console, GMB and analystics when the previous agency seem to have it all on their own accounts and are desperately trying to lock the client in? The client doesn't mind starting from scratch if he has but his GMB has a lot of reviews so Ideally we want to take control of it.