2017 MacBook Pro wont detect battries

So i attempted to use the ifix battery replacement kit to change my battery and i used a guide from about 2019 of this fellow using the guide to replace his battery in the same 2017 macbook pro. But when i got to the end and the time came to finish up and i try to turn it on it wouldnt work without the charger, and i think the problem is that he failed to mention that you need to unlock the ribbon cable on both sides before removing/attaching it and now im not sure if my logic board is broken or if my ribbon cable isnt working as it wont detect the old battery nor the new one? Any tips for testing/ figuring out whats wrong?