Google Chrome can either use system proxy settings or its own internal proxy settings. If it's set to use its own, it will bypass any AB Tutor website monitoring or logging policies applied as the traffic will not go via the AB Client local proxy. This can be fixed by setting Chrome to use the system proxy, so when the AB Client updates it, Chrome's traffic will go via the AB Client proxy. This can be done manually in Chrome's settings, however this isn't secure. The best way to do it is via Group Policy.
Google have made a zip file of ADM and ADMX files available from their support pages which can be imported and then the options selected from the normal Group Policy options. Alternatively, you can add the key manually:
Software\Policies\Google\Chrome\ProxyMode should be added as a REG_SZ (string) set to "system"
Once this has been set as described, the Chrome proxy will be locked to using the system proxy settings and will not be changeable by the end user.