@IanGoh My institution has tested but not implemented these Teams integrations, and I'm not sure what to make of the very sparse web_logs that we have related to these tools. My guess would be, as you said, "all this means is someone clicked on the link." Maybe there's some clue in the text of the URLs.
It's possible that there's a URL pattern in web_logs records that doesn't include the "external_tools/[id]" pattern, but I have not tried to identify it for Teams integrations. (I do know that a lot of the old Office 365 tool's web_logs URLs are LIKE '%url=https%office365-iad-prod.instructure.com%' and don't contain the external tool ID.)