launching stack in CloudFormation-Failed with ROLLBACK_COMPLETE Status

To troubleshoot what has happened, you need to go to the cloudformation stack, look at Events tab and trace the first failed event that has triggered the rollback. There might be a number of reasons why a stack might fail :

• there is an outdated reference in the stack
• you do not have permissions or access to certain resources mentioned in the stack
• deployment might have failed by incident for one of the resources
• etc.

[Update] I have run the same stack in us-east-1 with success and using these parameters. Please note that I used t3 instances for test. So the stack does not have any issues in deployment. You need to look at the Events tab and trace the error.