RSS feed by job listing category

Hi all,
I’m trying to setup an automated Mailchimp email to the workers for a client of mine and I was hoping to segment the jobs listings using the following filtering.

https://harperconstructionrecruitment.co.uk/?feed=job_feed&job_listing_category=labourers

But it doesn’t show up the category of workers, it shows up all of the worker categories. I know there was a similar question asked about 10 months ago, but that was for job types not job categories. Is that the same solution for this problem? If so, how can we get around the fact that we need to use the Broadbean plugin to pull in the jobs from a third party?

Thanks!