Here are the results for 3 posts:
1) new 4/6 correct results vs old 0/4

https://hidemyage.staging.wpengine.com/hydrafacial-md/
vs
https://beautyblackbook.com/hydrafacial-md/

right category id - 385 (daily skincare)

postID 7141 with primary_categoryID 1495 ( Beauty Products & Devices)
https://hidemyage.staging.wpengine.com/le-mieux-skin-perfecter/

postID 3490 with primary_categoryID 1497 (ANTIAGING SKINCARE EDUCATION)
https://hidemyage.staging.wpengine.com/snail-facial/

2) new 3/6 vs old 0/4 results

https://hidemyage.staging.wpengine.com/thermismooth-face/
Vs
https://beautyblackbook.com/thermismooth-face/

right category id 710 (LASER SKIN REJUVENATION)

post 7071 primary_categoryID 706 (body)
https://hidemyage.staging.wpengine.com/ultrashape-power-fat-burning/

post 6442 primary_categoryID (none)
https://hidemyage.staging.wpengine.com/what-is-dual-mode-microneedling/

post 5958 primary_categoryID 1495 (Beauty Products & Devices)

3) new 5/6 vs 1/1 (don't know why it doesn't show any other)

https://hidemyage.staging.wpengine.com/brilliant-distinctions-program/
vs
https://beautyblackbook.com/brilliant-distinctions-program/

right category id - 389 (Injectables)

post 7337 - primary_categoryID 2163 (BOTOX ALTERNATIVES)
https://hidemyage.staging.wpengine.com/rt002-by-revance/

Hope it helps.

As you see it's getting 60-70% correct posts. I can live with that (even 60% is a way better than 0%, haha) but if you want to find out the culprit I will gladly assist with testing.