Conversion or Body-Snatchers?

Welcome to a certain place near the equator on the third rock from the Sun.
In this place, it's citizens have a problem of the religious kind. It's called conversion and the knowledge of it after a person's death.

http://www1.malaysiakini.com/opinions/111088

According to authorities, these converts, or muallaf as they are called, had converted at some point in their lives and regrettably did not inform their families.

However in the case of Mr. Gan Eng Gor, who was said to be a Buddhist convert to Islam and was ordered to be buried as a Muslim by the Syariah Court, his family insisted that Gan had never converted to Islam, saying he had suffered two strokes and could not speak at the time of the alleged conversion.
 
The reasons are plausible, but honestly, is there really a need to body-snatch from grieving relatives?
I can't say for sure because I do not have much knowledge about Islam enough to criticize the authorities who help bury the dead according to their rites. On the other hand, I question their (the authorities) motives of doing so.

This is because, to my limited knowledge that is, when a parent converts to Islam in Malaysia, the children will automatically become converts themselves, with or without consent of the children. Another thing is that when that person dies as a Muslim and the children are not Muslims themselves, whatever property that dead convert has, automatically goes to the baitulmal.

Another question I want to ask is: If Malaysian citizens have a right to religion, why is it that Islam is the only one one can convert in, and not convert out?

Please feel free to correct me and educate me.