It seems possible but not the total answer. It could also be caused by a weakened heart pumping poorly (similar to hart failure) or to a screw up in harvesting the leg veins. Also if they took out a GOOD one that was pulling more than its weight and left occluded vessels to do the job, that could result in venous insufficiency and edema.
So either the doctor screwed up or not...and you will never know the truth.
My friend had a quadruple and the swelling was gone after 2 weeks...leg sore for months afterward though.
Leg swelling worsens in hot weather, so that might be a factor. Perhaps a diuretic might be a good idea...and the horrid elastic stockings <such FUN in humid 90 degree heat.