It is not possible to update the TestNG version beyond 6.1.1.
Any higher version leads do a failing test.
Must be investigated.
See the attached patch for a fix for this problem.
Essentially, the problem is that the InitializerExecutor only runs the Initializers once. The failing testcase was adding a new Initializer, but this was not being run as the InitializerExecutor had already run the default Initializers.
The solution is just to set the AtomicBoolean to false if the initializers are reset or changed.
The patch also upgrades to TestNG 6.8.