Directory permissions are not inherited for SQL trace files. SQL Server sets permissions such that only the service account, local administrators, and the owner can access the file because the trace may contain sensitive data. This isn't an issue to use fn_trace_gettable against local trace files since that is done under the context of the local SQL Server service account but is problematic when trying to access the file remotely from a SQL instance running under a different service account or one that is not a member of the local Administrators group on the remote server.

A workaround is to either add the SQL Server service account to the remote Administrators group or use the same service account.