Endpoints are not syncing between SentinelOne and Red Canary due to Deep Visibility being disabled. Deep Visibility is what provides endpoint data to Red Canary. Here is an article to see How Red Canary integrates with SentinelOne for more information.
Here is how you can find and enable Deep Visibility from the SentinelOne dashboard:
1. Navigate to the Sentinels page
2. Choose which group you would like to edit
3. Go to the Policy tab at the top
Scrolling down on the Policy page will lead to the Deep Visibility setting:
Select the box and save your settings.