Is there a way to log timeline activities on the platform level of salesforce?

CJ - What do you mean by the "platform level of salesforce"?  We do allow timeline activities to sync to SFDC activities - is that what you are referring to?

Here are a couple of the FAQs related to this capability for updating SFDC activities from Timeline:
Do Timeline Activities auto-sync to SFDC Activities? This is an option that the Admin must enable for each Activity type under Administration > Activities.
How often do Activities get synced to SFDC?  Activities are synced to SFDC in batches every 5 hours. If there are fewer than 50 activities created across your org, then they will sync at least once every 30 hours.

Hey Denise -- With our Salesforce stucture we work off of relationships. When I log an activity in timeline, it's syncing it with the activity section under the "Account" level in Salesforce rather than the "platform" relationship level.