Thank you Speakerphile and dbdynsty25 for replies.
The Pinouts Gide website has information that I have never been able to find on my own so It is very useful to have!
When it comes to the Boom Pro cable, I am using the V-MODA PC Mic Adapter so the M-100 becomes a 2-jack "PC" style connection. I am trying to set up the M-100 Mic the same as a this picture shows here:
The thing that is confusing to me is that I have the M-100 Mic set up the same as that kit but it isn't working. All the cables work but the Xbox just does not want to accept the Boom Pro.
So in the end, I will probably end up trying that kit to see if their adapter works any better than mine. And if that doesn't work, the Mix amp is probably the best option.
Your 3.5 to 2.5 being a four-pin is probably the issue.