I noticed that the List Groups API has a boolean field indicating if the group is deleted or not. But the API only lists groups if deleted = false.
Is there a way to have it list all groups, regardless if deleted equals true or false?
https://developer.zendesk.com/api-reference/ticketing/groups/groups/#list-groups
Unfortunately not, the group is removed from the list groups response array. Though if you call the deleted group directly, you'll still receive the record with the deleted key value of true.
Sorry for the inconvenience.