The two NetBackup domains are islands. The fact that they both use cloud containers might be largely irrelevant. It sounds to me as if you might want to configure NetBackup AIR between the two NetBackup "domains". The manuals describe how to do this, and there are plenty of posts in this forum regarding things that poeple forget or miss.
Of course I'm probably getting the wrong end of the stick. If you think that what you have done so far is right and should have worked, then I think you're going to have to explain in more detail what it is that you have done/actioned to create both builds, and then what it is you have done in terms of backups and somehow seeing/accessing/retrieving the backup data again. And why do think your actions should have worked? Are you following a guide/manual, if so, then please post a link to that manual and the page number/section that you are following.
