Hi! The database of users in your app is different that what Adapptio platform use. They only share user accounts for simplicity. So there is no concept of an application owner.
However you can solve the problem by adding a custom meta-data to an end-user account. You can do so by going to the application detail in the Adapptio Platform Admin. In the menu, open page End Users and click on the user you want to edit. In the meta-data section, select your environment and add a custom meta-data in a JSON format.

Then re-open your editor (so you are re-authenticated) and you should see your meta-data in the data explorer under the currentUser.data property.
Like this:

To use the meta-data you can parse them using the JSON_PARSE()
function. For example: JSON_PARSE(currentUser.data).role
.