I need help putting the unit back together

Another Dolphin Diagnostic story.

I need help putting the unit back together. I had to replace a broken side panel which involved removing the power cord from the motor inside the robot. Since Maytronics doesn't give away any secrets for repairs, I was happy to see how to do this one line. But as I was removing the red plug from the unit the two wires pulled out of the metal pin connectors. After connecting them back, the unit ran but only went around in small circles and it not longer reversed directions. I am not sure if it was even vacuuming at that point.
I reversed the wire connections knowing that there are only two pins that are used, but now the unit isn't vacuuming (yellow propeller isn't turning but turns freely by hand.) Drive motor is working but now it's only staying in one spot. I assume since the propeller is not turning, the unit will not move very far because of lack of suction.
I did open the motor compartment to make sure all the wires where connected but may have compromised the motor in some way. There was a lot of some kind of brown granulars inside that looked like dirt. But I understand that this may be some kind of desicant or DE. Another website described it as calcium corrosion from the motor (not sure what this meant). But, I do suspect that there may be water in the motor compartment, since it went to the bottom with not much coaxing. And is there supposed to be a separate gasket that you mentioned? If so, my unit didn't have one. Or do you mean that the "cover" rim needs to be sealed with silicone?

Can you please help me fix this since the local authorized Dolphin repair is out of the question. Last time I had it serviced, it was still under waranty but took a few months to get back.
I really appreciate it since I haven't been able to get my pool clean even with hand vacuuming. And summer is almost over!