Struggs – If neither the Motion that was put nor the Resolution of it at the EGM includes the name of the contractor who it was proposed would do the work and the quoted price is the same (or less), then NO I don’t believe that your Owners Corporation needs to convene another General Meeting just to use a different contractor.
As a matter of interest, what’s your E/C’s problem? It sounds to me like somebody who attends the Meeting/s should ensure that the wording of all Resolutions on Common Property maintenance includes something about timeframes for Work Orders to be issued to successful contractors; know anyone who could handle that?