The Chinese have apparently realized that the Moslems are a direct threat to the power structure. They need to back off on the Christians.
One group has people with government oversight, something like the ACLU wants the IRS to do here. The other group operates without the oversight, but only foreigners and those with residence permits in Special Administrative Regions (like Hong Kong) are supposed to attend.
However, my daughter had a lot of regular Chinese friends and students accompany her. If the authorities questioned them, any excuse such as the following would do:
In short, there is already more religious freedom in China than the ACLU wants in the United States.