To see coin balances and related coin metrics Workspace Owners/Admins can download an advanced analytics report (article here).

Inside this report, there will be a Member Activity tab. This tab will provide a breakdown of each member and related stats such as # kudos sent/received, # coins sent/received, # rewards redeemed, etc.

Note: To see a team member's current received coin balance, you'll need to subtract # coins received - #coins redeemed.