Interesting. The problem is in the John the Ripper package, not mine. I'm not the maintainer for the john package, but I'll look into it when I get the chance, as that is definitely a blocker for John the Ripper getting promoted to Extras.

I presume you are using FApMan to uninstall, and have "Autoremove unneeded (automatically installed) packages" turned on in the options?

Normally, apt-get would delete just the recoverlock package. However, FApMan, when that option is turned on, will also get rid of other packages which were installed earlier automatically which nothing else depends on anymore. Very useful option, but it can lead to issues like this. (The reason it never came up in my testing is I had john installed manually, not brought in automatically by recoverlock like in your case.)

First, I would double check if recoverlock is still actually installed (it's fairly likely that recoverlock got successfully uninstalled before the error came up when trying to uninstall john, depending on exactly how FApMan handles apt-get).

If it's still there, then as root, run:
(You can do 'remove' instead of 'purge', but currently 'remove' doesn't delete the file in /etc/sudoers.d/ - that's fairly harmless, but I'm going to fix that in the next release.)