Can emails be seen by users who have not connected their own email account via IMAP?

Can emails be seen by users who have not connected their own email account via IMAP?

Hello:

Our sales reps have connected their email to the CRM via IMAP.  Their email sharing is Public and we have set up data sharing for all modules (Public Read/Write). Our CEO, who is above the sales reps in our hierarchy, has not connected his email account to the CRM due to security concerns. Is there any way for him to see the emails from our sales reps without connecting his email account to the CRM via IMAP?  

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