Won't turn on after repair

We replaced the top cover unibody due to a faulty keyboard and to replace the battery. We used the ifixit video for this repair. Dismanting was fairly straight forward with the exception of disconnection of some of the connections being harder to remove than appeared in the video. After replacing the unibody we reconnected all the parts (which are many) and installed the new battery. We then attached the back cover and tried to fire it up. nothing……….. we decided we may need to charge the battery - so we did and got the Apple Chime as soon as we connected the power cord - we got no reaction from the new keyboard. We let it charge for an extended period - tried it - nothing. My gut reaction is that we damaged the Logic Board in the process so I’ve ordered one. Does anyone have any thoughts.

Thanks,

Danny J