It wasn't our network as one of the users wasn't on campus nor connected to vpn, they were at some event on that event spaces wifi, and also when they got home had the same issue. So it persisted across networks and geographic area. Other users who likely were on campus network, tried incognito without success. It appears primarily around internal-to-internal, however sometimes internal-to-external had the error too. Further investigating... and if users today are still having issues, to somehow instruct them to collect a HAR file for Google support... may be more complicated than them not sending an email... /s