Monitoring of cron job by external tool

I’ve been running multiple nextcloud installations for quite some time now, my home setup utilizes monit for some basic monitoring.
Till now i failed to set up a monitoring if the cron job has been run successfully. I know about the information in the admin panel, but i’d like to have something that can be parsed by monit or something like this.

The cron.php itself does not produce any output one could redirect to a logfile. The default nextcloud.log is still flooded with PHP array access errors.
The serverinfo-endpoint exposed by the monitoring app does not include information about latest successfull cronjob execution.

Have anyone of you set something up to monitor cron.php execution? Should i just parse the nextcloud.log for errors?