Environment Variables not succesfully Passed to qsub

I'm having trouble passing environment variables to qsub. I run the command:

qsub -cwd -N MPITEST3 -q main.q -pe impi_tight 2 -S /bin/bash -v PATH -v LD_LIBRARY_PATH -V /opt/intel/ClusterStudio/current/impi/current/bin64/mpirun -r ssh -np 10 /home/jamie_m/InterGen/interGen.out

But the job fails with "mpiexec.hydra: command not found". However, when I run which mpiexec.hydra on the node I launch qsub from I get the results "/opt/intel/ClusterStudio/current/impi/current/bin64/mpiexec.hydra" and I can see "/opt/intel/ClusterStudio/current/impi/current/bin64" in my path variable which I am explicitly passing to qsub. So I come to the conclusion that PATH has not succesfully passed to qsub.

I have read the solution on Pass environment variable to qsub jobs and I believe that I am correctly positioning the -v and -V flags but I am new to using qsub so I have tried moving these flags to immediately after qsub and got the same error. I have also tried with only the -v and only the -V as I was worried they might be interfering with each other. My understanding is that -V should pass all environment variables defined in the current session to qsub and so should be sufficient without explicitly passing using -v but I found the man page a bit unclear when it says "Specifies that all environment variables active within the qsub utility be exported to the context of the job". What does active within qsub utility mean?

I can run this program using mpi over multiple cores within a node and interactively using qrsh over multiple nodes so I don't think the problem is with mpi. Any suggestions greatly appreciated