Volto and Sentry backend reporting

I've been trying to get Sentry integration set up with Volto. Frontend reporting is working well, but I never see any backend (ie nodejs server) exceptions coming through to Sentry.

I made a more detailed issue in collective/volto-sentry/issues/7.

I was wondering if anyone had managed to get backend exceptions working with sentry?

The docs talk about backend options and the code suggests it's possible, but I've had no success so far.