The precise function is not documented, but purge-broken-files code doesn’t obviously do any recreates. These are different functions anyway. Recreate is a database reconstruction done using destination files. –list-broken-files and –purge-broken-files sound like analysis and removals of broken files currently there.
I’m a bit surprised –verbose isn’t complaining. New log system with filters says it should be gone by now. There’s some information in that article on the effects --verbose used to have before the new log system.
strace not finding anything is really weird. That should trace every system call, right? Windows Duplicati generally comes in paired processes, where the parent is mostly to launch a child with the latest update. Mono is possibly different in process organization. There are usually two but I’m not sure if it’s equivalent.