No, you will not be charged twice if your team member views the same contact within 90 days.
You (or your team) can view a given contact multiple times in a 90-day period, and you will only be charged once for that contact.
You viewed contact-A on October 12, 2019. Credit charge = 1.
Your team-member-B views the same contact-A on December 7, 2019. Credit charge = 0.
Your team-member-C views the same contact-A on January 3, 2020. Credit charge = 0.
Your team-member-D views the same contact-A on January 31, 2020. Credit charge = 1, because this is after 90-days from the date (October 12, 2019) on which someone from your team first viewed this contact.