Do you receive any errors when you try to open 32 workers right off the bat?
Before running matlabpool 32 or similar, can you please run setSchedulerMessageHandler(@disp). This will print out what MATLAB is trying to do and there may be a helpful hint in there.
Lastly, I would suggest for you to shut down MDCE on each node and then to restart it. After doing that, if you are using MJS, restart MJS and the workers in the Admin Center.
NOTE: When starting the MDCE service back up, run it with the -clean flag to make sure it is not being held back by previous issues: mdce start -clean.