Assuming that I got everything correctly, the customer wants to archive only certain VMs to tapes, right? If so, there are two options I can think of.
1) Create additional backup job with the desired VMs included and specify the newly-created job as a source for backup to tape job. However, in this case, the customer will need both additional space to host backup data and time to run additional backup job.
2) Create backup copy job with short retention and use it as a source for file to tape job. Nevertheless, in this case, once the backup copy job exceeds specified retention, the full backup will start moving on daily basis. Thus, the new full backup will be copied to tapes each day.