Just pointing out that the xml output is perfectly fine JUnit output, which was the source of our confusion. We were having Jenkins process the xml reports as TestNG, which fails.
Is it really a problem? You’re still running TestNG, the results just happen to be in JUnit format. All the data is still there. Once we know what the format was, it wasn’t a problem for us anymore.
You are correct, I probably didn’t read or understand the answer. I needed to change from the jenkins TestNG publisher to the JUnit publisher and everything worked.