There is no function to BCC someone into a ticket in Deskpro, by design. Consider what happens if a person who is BCC'd onto a ticket replies to a ticket message: if Deskpro added their reply to the ticket then all other users/agents could see the message. This defeats the purpose of a BCC.

Alternatively, you could:

Forward as a New Ticket

• This can used to forward a message or whole Ticket history.

Create a Linked Ticket

• Linked Tickets act like an independent Ticket, but it’s linked to the original Ticket making it easy to stay on top of what is going on with the issue. You access linked tickets from the Linked Tickets tab on the ticket properties panel.