Automator service not working in Mojave

I have an Automator service that was working fine until I updated to Mojave, but now it only partially works.

It is supposed to split a multi-page PDF, and then convert the pages to jpegs - it does the first bit, but not the last.

I see other people have had similar problems, but didn't see a solution, and the thread has been closed - any progress on this?