I assume that by LC-OpenLab you are talking about OpenLab Chemstation Edition (since you are doing fraction collection).
I'm puzzled as to why you want to do this via this via the command line. OpenLab Chemstation Edition supports the queueing of multiple sequences. If the second sequence contains different methods, they will be loaded automatically. If you want to allow some equilibration time after loading a new method, then you can do this directly in the sequence parameters for the sequence.
Is that what you want to do?
There's no simple way of loading methods and sequences from outside of OpenLab Chemstation, that's not to say that it isn't possible!!