eDiscovery Searches including extra documents

Running searches in Advanced eDiscovery, if the location includes both a SharePoint/One Drive site, and Exchange, for example if I've created a Custodian and identified their EXO/ODB site, and added an additional Team or two, and then try to simply point to the Custodian in Search and search for, say "kind:microsoftteams", I would expect it to return all of the Teams-related messages in the mailboxes, but have zero hits from ODB/SharePoint. In fact, it hits on EVERY document in SPO/ODB and adds them all to my search results. I see the same thing in Core if I include a SPO site in that search, and I also see the same thing in reverse. Searching a Custodian for a metadata field specific to SPO, like "filename:employee" returns every item from the mailbox. Seems like a bug, can anyone confirm that it is, and if we should expect a fix for it?