twocan ...
My hunting partner/brother and I split the land with a tree, fence, point of a hill, etc to determine who shoots what. When we set up a stand, he places the caller where we think it should be in accordance with our positions and we pick our landmark at that time. For example, we set up and this time I am on the right side of the caller. We picked a tree down in the valley and visualize a straight line from the tree to the caller. If a yote shows up to the right of the line and I have a good shot, I take the shot. If a yote shows up on the right side of the line and for some reason (might be out of range) and it crosses to the left side of our line, it is now my brother's shot to take. we have always enjoyed this arrangement and get some laughs out of it too at times.
Now you said you are shooting a 9mm rifle coyote hunting and your partner uses a shotgun? Maybe you guys need to at least consider higher powered rifles for this type of hunting. If you do not want to outlay too much cash, then consider a Handi bb in .223. These have a good reputation for good accuracy and will give you two guys shooting ranges only limited by your shooting abilities in your woods type hunting. There should be more available shooting opportunities for the both of you unless I am missing something here.