What seems to be happening is that you are using the older version of the Run Test Set Scheduler. In the old version the documentation is incorrect. In the documentation it is stated that you do not need to use /h: or /l to specify the host the test is run on, but this is incorrect. If you are using the old version of RunTestSet.exe your code should look like this:
RunTestSet.exe /s:http://QC10SERV:8080/qcbin /d:TestProject /u:qcadmin /p:qcadmin /f:Roottest /t:automated /l
Or
RunTestSet.exe /s:http://QC10SERV:8080/qcbin /d:TestProject /u:qcadmin /p:qcadmin /f:Roottest /t:automated /h:exmachinename
Another option would be to install the latest version of the Run Test Set Scheduler which does not have this issue with the /h: or /l. You can get this file from your support rep. You can tell which version you are using by the name of the exe. RunTestSet.exe is the old version, RunTestSetScheduler_ALM.exe is the newer version.
In the newer version if you were to use the code below the test should run on whatever machine it is set up to use in the QC/ALM UI at least as the documentation reads, but from what I have seen the test will execute locally if you leave out the /l /h: or /g: parameters.
RunTestSetScheduler_ALM.exe /s:http://QC10SERV:8080/qcbin /d:TestProject /u:qcadmin /p:qcadmin /f:Roottest /t:automated