Hi Brian ,
looks like a duplicate Question .
Have you done the Rf site survey before the deployment ?
AP selection is a client decision. I don't think there is anything to set in the ZD/controller for the client to connect to an specific AP.Each client has its own way to connect the AP depend on s/n, interference, signal strength (RSSI) etc.
We should deploy the AP correctly with 15% cell overlap with proper power levels.
There could be alot of reasons for this behavior .
1.Laptop/Device NIC drivers
3. very high Tx power on far end AP
4. Poor AP cell overlap ( It can cause roaming issues as well)
Try to disable lower data rates on the far end APs.
Update the driver of the client devices.
See if it helps .