In case this helps someone in the future, I wanted to finish up this thread with what fixed our X5 not locking.

Recapping the thread to one post:

• The X5 wouldn't lock by key or by center console. Fob battery had been dead
for some time.

• The center console button does nothing, no sound or activation of the locks.
It doesn't seem like this button had liquid poured on it, it wasn't sticky.

• The Key feels like theres no resistance turning left or right in the driver door
lock (not stuck). No sound when turning the key either way.

• We hooked up an ODBII computer and tried to actuate the locks - Failed.

• Fuzes all are good - no blown fuzes. The 12V battery is less than a year old.

• One thing I failed to mention in my original post - the driver door lock stem
would not budge. Press on it as hard as you wanted to and still it wouldn't
move.

• As recommended we bought the driver door window switch assembly which made zero changes so we sent it back.

What ultimately fixed the locking issue:

Installing a new door actuator. When I took off the door lock, the door lock spindle came out in several pieces. I bought the repair kit on eBay, which along with the new door actuator we now had beeps when it locked with the key! We never had that before since I acquired the X5. Surprise! Surprise!

After having success with the door actuator and door lock spindle. We thoguht we were done. Nope... The center console door lock button would only unlock the car, but not lock it. Buying a new center console button fixed that issue.

While I was in there with the door panel off I put a little lite grease on the power window guides, as well as the door handle spring. The stainless steel zip tie was still in the location i put it in when the door handle broke. Thats a great mod that everyone should do!

Hopefully the X5 is done with needing parts for a while. I rarely drive the X5 (we call it The Tank) its here on the property for anyone who needs a car or needs to tow a small trailer etc... I think i'm going to put a note pad in there for any strange sounds or anything not working from now on.

Thanks to everyone who offered their help!