Unfortunately, the law cares little about "attachment." The kicker is the Constitution adopted by this church, which stated that the church held title in trust for the denomination. That was a perhaps stupid provision, but it is apparently controlling.
I understand the court position, but also understand the people wanting and pursuing every possibility to keep it.
Depends on the state. Some states have the same real estate law for all people ("neutral principles of law" states). Other states have special rules for liberal denominations.