MacBook Pro 13" Retina Display Early 2015. My keyboard stopped working but my trackpad is still working fine. The only...

Hey I am having a similar issue. My keyboard stopped working but my trackpad is still working fine. I took it to a repair place and they said that putting in a new keyboard did not fix the issue. They now want to replace the logic part on the mother board and reprogram it. I told them that it could be the cable for the track pad and they said that when they swapped the mother board the keyboard worked fine so it has to be the mother board. When i plugged in an external keyboard, it also didn't work. Not sure what to do. Should I still try to replace the trackpad cable?