Even if the sourcecode was released that wouldn't solve the problem. Unless M&B uses some kind of dynamic memory relocation scheme a memory patch would be able to manipulate\read the objects in the game. It would not be easy, but it could be done.
The problem is that the way combat works in m&b makes it incredibly timing sensitive. In any FPS, you just make sure that the one you're trying to kill is roughly in the middle of the screen, and click the mouse. Even at quite high pings he will not have moved far before the information that you sent a bullet in direction x from from point y reaches him or the server.
In M&B it is quite a different story. I am not familiar with the inner workings of the game, but i will take a guess that an attack is recorded in a "animation x was initiated from coords y with weapon z, the character initiating the attack was heading in direction i with j speed, now check if any other dynamic (non terrain) objects are within the scope of the animation, if so: Deal damage, else ignore".
As you can see this is whole lot of information too keep track of, remember this has to be done for every character on the battlefield, with possibly an exception for horses.
To make this easier to transport as the internet is crammed with torrents, we must pack light, I would use an initial position in three dimensions. I don't know how many coordinates that are possible in a M&B battlefield, but i can imagine that this would make for three rather large integers. To avoid having to report my position every millisecond to avoid stuttering, I'd only send my velocity changes. I would also have to report actions like mounting/dismounting and attacking/blocking.
So far so well, now for the bad part: to make sure that you got all my velocity updates this would need to be a tcp connection. tcp connections are slow. One could always write your own network stack, I've done it, but i wouldn't recommend it. One could possibly use some existing framework like Directplay, but I am not sure if you can dictate what transport protocol to use.
What I am trying to say is that I think the whole debate has wrong focus. The problem is not getting you hands on the sourcecode, but the technical limitations in the internet and it's protocols. In addition to insane amount of information that must be sent to make this internet playable. You must remember that all characters, the NPC ones too, must have instantaneous status updates on the battlefield. But nothing would make me happier that if someone proved me wrong.