Hi,
With a 5DS license, one DS channel is enabled from each controller from the card. Even with 5 DS license only in 20x20 LC, you should be able to assign DS channels from different controllers to the same DS bonding group (wideband-cable interface) so you should normally be able to do DS bonding with such a group.
Take into account that I'm not able to fully verify this locally since all my linecards are licensed with 20DS, but I believe it should be possible. I would suggest to have an official answer from your Cisco Sales Representative to be on the safe side.
Regards.