I hadn't expected there to be no output at all.
I've extended
zotero-debug-log to do live log capture. It won't catch the crash itself of course, but it catches enough of the lead-up to be useful. Best I could do for Windows log capture.
I wouldn't dream of developing on Windows, but some bugs seem platform-bound and I need a way to diagnose these things. Popping open the console made Zotero absolutely intolerably show -- a test that was supposed to take a few minutes grew to an ETA of 4 hours before I killed it.