Thank you so much for sharing this! It also worked for my sub accounts.
The only thing is I still have issues with connecting with GMC due to domain claim error. For context, we revamped our website and migrated to two new Shopify stores. We then transferred the URLs from the old stores to the new ones, but now GMC is saying that the domain have been claimed. I wonder if anyone else have had the same issue and know how to solve it?