I did some more reflecting on your plea and thought this might help.
There are ways and means of addressing falsehood but bear in mind that it is only your duty to present the truth as you see it and it is up to them to believe it or not:-
2:272 Your responsibility (O Messenger) is only to show them the Right Way (and not to make them walk it). He has established Rules for attaining Guidance. (O People) Whatever good you give benefits your own ‘selves’ when you spend for the sake of God. Any charity you give will be repaid to you, without the least injustice. [God's Laws for Guidance: 2:2, 2:26, 4:88, 5:46,
7:52, 13:27, 14:27, 20:123, 27:2, 28:50, 31:3, 39:3, 40:34, 40:74]
Let me give you an example of how to present your case. Find a verse they have quoted and look at its context; you will find that 99% of the time it is taken out of context and/or misinterpreted. Look at one such quote you gave:-
“Allah says (interpretation of the meaning): “He who obeys the Messenger has indeed obeyed Allah...” [4:80] Allah described obedience to the Prophet (peace be upon him) as being a part of obedience to Him. THEN He made a connection between obedience to Him and obedience to the Prophet (peace be upon him): “O you who believe! Obey Allah and obey the Messenger...” [4:59] “
The “THEN” means after 4:80, not going back to 4:59 which is what they have done! Read the context:-
4:80 Whoever obeys the Messenger, obeys God. But if any turn away, We have not sent you as a watcher over them. [5:44]
4:81 They express verbal allegiance to the System, “It is Obedience!” But when they go away from you a party of them spends the night in planning against the Belief System you preach. They discuss ways to corrupt the Message. God records what they plan by night. Ignore them, go ahead with your Program and trust in God (6:107). God is Sufficient as Guardian.
4:82 Will they not then, try to understand this Qur’an? If it were from other than God they would surely have found in it much contradiction.
4:83 The Book of God provides easy and practical social Guidance. There are people who spread rumours pertaining to safety or fear. Those who hear rumours shall refer the matter concerning public safety and threat, to the Messenger and the government officials. Those who are engaged in obtaining intelligence will indeed know what to do with it. Had it not been for the Bounty of God and His Mercy, most of you would still be following the Satanic elements.
They were supposed to be following the system of government, abiding by the conditions of the ideal society created by the Messenger, based upon the Revelation he had received from Allah called the Quran. There is no reference to the sayings or practices of the man, Muhammad, but to the Quran; “ponder over the Quran”, not blind acceptance of hadith!
Let us now look at 4:59, in context:-
4:58 God Commands you to entrust your offices to those who are capable, competent and sincere. They shall rule and judge equitably. Give your trusts to whom they belong. The Enlightenment from God is a blessing for you. He is Hearer, Seer of all that transpires in the Universe and in your society.
4:59 O You who have chosen to be graced with belief! Obey God and obey the Messenger, the Central Authority of the Divine System, and those whom the System has appointed as office-bearers. If you have a dispute concerning any matter, refer it to the Central Authority. If you truly believe in God and the Last Day, this is the best approach for you, and more seemly in the end.
4:60 Have you thought of those who claim that they believe in what has been revealed to you (O Prophet), as well as in what was revealed before you? Yet, they resort to Taaghoot (priests and monks of any religion) for judgment in their differences. They had been commanded to reject them but their rebellious desire misleads them far astray.
4:61 When they are told, “Come to what God has revealed and to the Messenger”, you see the hypocrites shunning him completely.
If “obey Allah” means follow the Quran, “obey the Messenger” means follow the hadith and sunnah, then what about obedience to “those in authority”!? Surely if we are to take the meaning of hadith of Muhammad as binding upon us in an act akin to worship, then we need to do the same to the hadith of Omar, Saladin, Osman the Magnificient, Sadam Hussain etc.! Either that, or we read the context of the verse and see it is again referring to following the Quran. First by following the Messenger who was the means for the Quran to be revealed to us, and then follow those who attain power after him who also use the Quran. 4:61 shows the attitude of those who are invited to the Quran and turn away in arrogance; “my sunnah and hadith is better than the hadith and sunnah of Allah” is what they are saying, nauzubillah!
I will leave the rest for you:-
Allah warns us not to go against the Prophet (peace be upon him), and states that whoever disobeys him will be doomed to eternal Hell. Allah says (interpretation of the meaning): “...And let those who oppose the Messenger’s commandment beware, lest some fitnah (trial, affliction, etc.) befall them or a painful torment be inflicted on them.” [24:63]
Allah has made obedience to His Prophet a religious duty; resisting or opposing it is a sign of hypocrisy: ”But no, by your Lord, they can have no Faith, until they make you [Muhammad] judge in all disputes between them, and find in themselves no resistance against your decisions, and accept (them) with full submission.” [4:65]
Allah commands His slaves to respond to Him and His Messenger: “O you who believe! Answer Allah (by obeying Him) and (His) Messenger when he calls you to that which will give you life...” [8:24]
Allah also commands His slaves to refer all disputes to him: “... (And) if you differ in anything amongst yourselves, refer it to Allah and His Messenger...” [4:59]