I was testing some of your APIs and when I call https://developer.zendesk.com/rest_api/docs/support/tickets#create-many-tickets with an invalid body, it returns 200 OK while there is an error.
Create Ticket and Create Ticket Async handles this use case properly.
The body I posted with Create many tickets is tickets with only subject and no comment (which is a required field).
"subject": "My NEW printer is on fire!",