Segregating multiple emails in an Outlook account

Hello world,

I am at the start of my company's Hubspot journey, I have a small issue regarding email setup and i was hoping someone could give advice on overcoming this little hurdle. I have two colleagues that use our company email as their primary email in Outlook, they have a secondary email within that Outlook that is not associated with my company. How do i have their emails connect to hubspot without Hubspot pulling the info from their secondary email address? 

Regards,

Ben