I want to echo something that Dan said.
I went and bought a replacement cable from Ebay for about $13 AUD. It was a bit longer and had more slack. The part was not a genuine Apple part. It worked 90% of the way just like you said, but the haptic feedback was not there.
Unfortunately I had work to do and didn’t want to waste anymore time. I went to apple store and they immediately agreed it was a trackpad cable issue. They charged $15 for the part and $120 for labour. They actually did the job first to confirm & identify that was the issue (without requiring me to deposit my laptop and put it in a queue for a week). It worked.
So long story short. Small things on ebay despite same part number are unlikely genuine. Same on iFixIt, Louis Rossman Repair, and most other sites - specifically if they claim new condition. Only Apple sells genuine parts and not to the public.
You can however buy used parts that are genuine. Powerbook Medic is good for this.
Anyway this is an unfortunate situation. I expensed the repair on my company dime since I use it exclusively for work despite it being personally mine. But I understand not everyone can do this and so I hope someone will find it helpful when they look for the trackpad cable replacement to know that there is actually a difference between a genuine and a non-genuine part. Which sucks.