I have three sites on the same server setup with the Sentry extension, all with different Sentry DSN's, however, the error from each site are going to a random DSN and not the configured one.
It appears that it is selecting one of the DSN's in the configuration at random and sending the error to that DSN.
I have confirmed they all have different DSN's configured in the web admin of each for the exception log.
I am seeing errors from all three sites in all three projects in Sentry.