doublebogey7
Head Pro
They have not agreed to waive a rule of golf, in fact we don't know even if they have agreed to waive a term of competetion. It sounds to me as if they did not know they should have been playing from the whites and under Rule 1.3b players are only disqualified if they agree not to apply Rules they know applies.» If two or more players agree to ignore any Rule or penalty they know applies
and any of those players have started the round, they are disqualified (even
if they have not yet acted on the agreement).
Applying your logic if I have never read any of the Rules of Golf I cannot be penalised for infringing them.