MIM -Wait with JCL Failure

I have a MIM transfer from Mainframe to Windows that has failed 3 of the last 10 times it has run.  It contains a -wait 900 code to wait 15 minutes for a response from the server to say that the transfer was successful (or not).  Looking at the errors received, it is not waiting 15 minutes before getting a timeout (Exception Code 4000, Timed out waiting for response from remote directory service), and the file was actually transferred successfully and received on Windows.  So I am perplexed by the error.