It seems you have backwards, Muslims did not keep Mohamed Hegazy ( the 16 years old kid) to rewash his washed brain. BUT The church kept kamelia Shehata (25 years old adult) who converted to Islam, without any pressure, The church kept her (or killed her as Waffa Konistanteen) and then you are talking about freedom of religion.
Conclusion, The church keeps the converted Muslims and the converted Christians.