Loyalty doesn't mean you nod at the decision of a leader even when you know from your personal exposure or expertise that this opinion may be wrong. To be loyal you must know you are planted by God to give the leader the full view and wealth of your expertise.

After you have contributed your thoughts clearly explaining your position backed either by the scriptures or through inductive reasoning which compares past experiences to find established patterns, you allow for a decision to be taken. Once a decision is made you maintain unity.

Except it is a case where your fundamental beliefs or you are being asked to do something which is illegal or morally bankrupt, which in that case you are at liberty to walk from the group. Keeping silent without making your thoughts known is not humility, it is timidity.

Simply because your opinion was not accepted in the light of other contributions, you decide to disrupt the group is rebellion. These two things you must do, make your opinion known backed with scriptural truth or emperical data and then make unity in pursuit paramount.