Is there a way to cc someone on an e-mail notification?

The best way to do this is to create a formula List-User type field called [employee and their manager].  Then that field will appear on the drop down choice for the recipient.   Duplicating notifications is a losing battle to keep them in synch - double work, so you are right to suspect that there is a better way.
here is the help on a List-user formula
https://www.quickbase.com/db/6ewwzuuj?a=dr&r=fx&rl=tg