I agree the Bylaw should never has been passed if 2 of you were against it.
BUT assuming this Bamboo is within the lot bylaws cannot be retrospective and so the bamboo has got a get out of jail free card.
Also even if this was not the case the EC would have to prove at CTTT that the bamboo is causing a problem and before they could enter your lot to cut it down they would require a ruling from CTTT for the EC to take this action.