To build on crippsb's first solution,
- Create a second connector with a Users DN set to the other OU (e.g. ou=Other Location,dc=domain,dc=local)
- Create a group in your "own" OU that contains users that you need from the other OU (e.g. cn=Outside Helpdesk Users,ou=My Location,dc=domain,dc=local)
- Set the Search Filter on this second OU connection to (&(objectCategory=person)(objectClass=user)(memberOf=cn=Outside Helpdesk Users,ou=My Location,dc=domain,dc=local))
This should find all members of the "Other Location" that are members of the group called "Outside Helpdesk Users" which you have created within your own OU. This should not require any permissions for you to modify the other OU.
An alternative solution would be to modify your original connector by expanding your Users DN base to include the next higher up part of the tree, perhaps the domain root. Set your search filter to a group you create in your own OU that contains ALL of your clients, both those who are contained in your OU and in the other OU.