This seems to work just fine - thanks!
I now need to figure out how to use this in a way that does not affect my ability to recover from replication issues. The problem: If there are replication problems, there need to be a common (between primary and secondary server) snapshot to be able to (manually) recover. If I run rollup on both servers, the snapshots that are kept may not be the same one. So for now, I'll stick to running it only on the backup server.
I now need to figure out how to use this in a way that does not affect my ability to recover from replication issues. The problem: If there are replication problems, there need to be a common (between primary and secondary server) snapshot to be able to (manually) recover. If I run rollup on both servers, the snapshots that are kept may not be the same one. So for now, I'll stick to running it only on the backup server.