Live logging is the only debugging tool SmartThings provides.
I knew that the message you both were seeing only happens when sirenStartTime has a value and tapping off should have fixed the problem because it sets it to null.
I remembered seeing this post so I knew that SmartThings broke the ability to clear a state value by setting it to null.
It sounds like SmartThings fixed the issue they were having so the original version of my DTH is probably working again.