How to move a post in Vacancies so it appears in News/Events?

This is basic WP functionality, it’s not dependent on a plugin.

You need to locate where the vacancies post type is registered and add the category taxonomy to the taxonomies argument:

'taxonomies'    => [ `(your job type tax and any others)`, 'category' ],

This should get the categories meta box onto your post type’s edit sidebar. However, it’s quite possible that there are other factors controlling what’s output to your archive pages.

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