Killing parallel processes?

In 12.1.0.2 on AIX 7.1, I needed to export a few schemas that were larger than the local disk space available. Since on-the-fly compression is no longer feasible without Advanced Compression, I used an NSFv4 mount point.

There was some issue (I don't recall -- it was in January) that I needed to kill the expdp. Ran it again with no problems, and all's well until today when I saw that the NFS mount point was still up and I tried to umount it. There are 7 files still open on the remote server from each of 7 parallel processes on the local database server. The files are named ".nfsxxxxx". I'd like to close this mount point, so I see that I have a few options:

1. Kill each parallel process. This database does not normally utilize parallel during the day, with only 1 query using it over night.
2. Bounce the instance. Scheduled downtime is in 6 days (just missed yesterday's window). This is a primary in an Active DG config with 1 physical standby.
3. Stop the NFS client. Nothing else is using it.
4. Stop the NFS server. Nothing else is using it.

The safest to me seems to be the instance bounce. But it's the most work, too, as I need to involve application folks.

I've killed parallel processes before, but only on test instances where I didn't care what the outcome was. There's currently 64 parallel processes (the maximum for this instance, IIRC).

Stopping NFS seems...messy. Unsure how the parallel processes will handle that.

Thoughts?