I ended up taking a snapshot and purging the files and everything appears stable. Because there were over 975,000 files, I used the following command to purge them;
for f in imfile-state*; do rm "$f"; done
In total it took around 30 minutes or so to complete - I would periodically check progress from another ssh session and run;
find . -iname "imfile-state*" | xargs ls -lrt | wc -l
-and also
df -h