There is two related issues for improving this functionality:
This ticket is to merely fix the text labels. The `Owner` field in the GitHub App credentials entry by looking just at its name suggests the owner of the app, i.e. a user or the org that has created the app. In fact, the value should be the user/org that has this app installed, as description suggests:
BTW there is also a typo in the description. It should be organizations not organisations.