"that shows the faithfulness of these brothers to still be going to the meetings even without song, prayer and bibles! no other religion would do that!"
This remark is quite typical of Jehovah’s Witnesses and reveals a gross ignorance about other Christian churches around the world. Almost all of JWs get their information about other churches from Watchtower literature; via Awake articles. There, you will find the most sordid stories about other churches that have been cherry-picked by the writing department for their scandalous nature. Therein lies the problem.
Jehovah’s Witnesses receive very limited, selective information. One could almost compare it with the kind of information that the state run news services of the Soviet Union would present to their citizens: information which painted the West in the most decadent light, and then presented "Mother Russia" as always smelling like a rose.
Most JWs are satisfied with the selective information they receive from their "Mother Organization". Many of them would be quite surprised however, to discover that they have been given only a tiny piece of the picture.
You may want to begin gradually, by presenting some seeming innocent information that might begin to open their minds. For example: go the the library and find some books on Christian history; particularly those which deal with the nineteenth and twentieth centuries. You will find countless historical accounts of Christians in other countries who showed a faith equal to, and sometimes surpassing that of JWs.
Here’s a couple of examples that I discovered while doing my own research: there were Christians in China who were translating Bibles long before the WT Society came on the scene. There are currently millions of non-denominational Christians in China who meet secretly in private homes; often risking imprisonment.
In India, there are currently hundreds of thousands of Christians who are being persecuted, beaten, and jailed over their refusal to comply with various political affairs, and their refusal to discriminate people based on the caste system. Does the WT ever mention or compliment these people? No way.
What does all of this have to do with the Mexico / Malawi issue? I believe that you first need to kindly educate the average JW on things that they do not know about other Christians and the faith that they have demonstrated. JWs live with a false illusion that they have been the only people to refuse to compromise their faith. History proves them false. If you kindly share some of the many historical examples with them regarding the uncompromising faith of other Christians around the world, it may begin to open the door to their stubborn and closed mind.