When you reached out to LinkedIn to confirm that the appropriate permissions were selected, was this the list: Campaign Manager, Account Manager, Company Page Admin, and/or Lead Gen Forms Manager?
To clarify the question regarding partitions, you'd want to go to Admin > Workspaces and Partitions to verify whether you have partitions set up.
To learn more about workspaces and partitions, please reference:
Typically, the first two steps that are given when this issue appears is to try:
-Re-authorizing your LinkedIn Account in Marketo -Deleting your LinkedIn service, then creating it once again
If you have tried both of these steps, and you’re finding that leads are still not syncing, please open a support ticket and one of our Technical Support Engineers can investigate further.
... View more