From my experience, you will not be able to find out who is the owner...
Seems like you have been deleted from anyone.
The only chance may be if you have the organization ID or at least name and ask your Sales / Meraki SE, if they can help you.
But wen have got two MR´s in our storage and are not able to claim them,as they are already. But we don´t know where and who did it.
Sales, SE and support are not allowed to tell us. No chance at all to find out.