I think ZBA did the right thing; you can only stretch zoning so far.
It's amazing the lengths the Trinity group were willing to go to in order to avoid merging with the healthy, growing congregation at St. Peter's, an idea that was floated over 5 years ago. The writing was on the wall, having occurred already with the Presbyterian and Catholic churches, but they chose to ignore the obvious.
I doubt if HWS would want the facility since they have their own chapel, but it was already off the tax rolls.
Just trying to grasp what it is your trying to say. The two Catholic churches (St. Stephens and St. Francis) are still here and the Trinity folks have been trying not to just abandon their church but find a use for it. So, they merge with St. Peter's. Great. So what do you do with the property?
Stretch zoning? what do you mean by that? A use variance has clear and deliberate criteria and I believe Trinity could have viably argued each and every point of it. This should have been tabled until public feedback was received and I bet the next hearing would have been more positive. Zoning is just rules put forth at a set point in time based on what a certain group thinks is in the best interests of those having a stake in the outcome.
So again, the results will speak for themselves but I guess some don't mind a vacant property rotting away in their neighborhood.