How to find account owner for Android app in Google Play Developer Console?

I would suggest you to search your gmail, google did send you an invitation email with owner email address in it the title is something like "Invitation to share a Google Play Developer Console Account"

If you can gain access to the email account specified in the "Email address" field of the Account Details page, search that inbox for emails from "Google Billing ([email protected])"

I found several emails about payments through the Google Wallet Merchant Account associated with the Google Play Developer Console. Those emails contained the email address of the Play account's owner.