This will be a really easy fix, we just need to include the engine in the name of the workflow file.
When addressing this, it would also be a good idea to look into versioning the generated files as well. This way, if a user needs two or more sets of unit tests using the same engine which require isolated environments, these files won't overwrite. An alternative to this approach would be to append new content to the first testQL created for that engine. If this extra part doesn't get cleaned up, I will address in in a separate issue.