Jamal, whether I can qualify as one of your 'respected experts' is doubtful but as an EX 1 user I can try and help you.
I always connect two mics to separate inputs as they seem to operate independently. In my menu setting I have it set to CH 1 & 2 and I get individual audio on each channel. It occurs to me that you may have the switches set incorrectly that are situated beneath the XLR inputs. Forgive me if you know this but unless the mic has it's own power supply the switch has to be set to 'mic + 48V. If the mic has it's own supply then set the switch to 'mic' which is the middle setting. Then there is 'line' on the left side for an amp input. However I don't believe that this is your problem, it's just an idea.