Anyone else had any issues with oiiotool producing different results to hoiiotool?

I have some Karma renders with AOVs that I'm trying to convert because the client is using a display referred workflow.

I've noticed that the -a flag seems to work with hoiiotool but corrupts the subimages with oiiotool.
It could be that oiiotool hasn't compiled properly or something, I installed it with with vcpkg.

oiiotool seems to work fine for everything except the subimages, which is why I've only just noticed the problem as I haven't needed to use it for anything except the beauty until now.

I know the obvious solution is to just use hoiiotool instead but it's quite a bit slower as it's using an older version that doesn't support the parallel-frames flag.