Yes you can. There is no conflicting issue there. HOWEVER, there are performance considerations you will want to consider putting Veeam and NBU on the same server.
I would recommend you check Veeam's documentation for recommended HW specs, as well as NBU's for your environment (NBU Performance tuning Guide) and see how you rserver stacks up.
You (ideally) would want to put veeam on it's own box as with some of it's advanced features like compression and dedupe, would take away from the performance of NBU. NBU just needs to come in and backup a directory keeping your Veeam backups.
I think, and you want to read the manual, but you can install Veeam on a virtual guest, and use SCSI Hot-add to backup the guests. Backups are then saved to a share that NBU picks up.
