Perhaps you accidentally popped off the spring contact from the main board. I had done this myself and had to search for quite a while to finds out the antenna locations in the phone. I answered my own question and provided an image that shows where the antennas and contact points are, and labels them so you know what each one is for in my answer. See this question: What antenna is this? I can't seem to find info online..
Found the answer on my own finally. Attached is the antenna spec sheet provided by Motorola to the FCC, just in case anybody else might have a need for this information down the road.
This is in the battery replacement tutorial, why would you want to remove the MOBO along with the battery? I’d consider the battery removal quite essential if the goal is to replace it.