Here's Mass MoCA's Joe Thompson in The New York Times earlier this week:
"Mr. Büchel has not worked on the show since early last December, when he returned to Europe to attend to other projects and left behind a list of additional objects that he wanted the museum to find. The list included one item that Mr. Thompson described as a final straw: the fuselage from a large jetliner, like a 767, that Mr. Büchel wanted to be burned and bomb-damaged and then hung from the ceiling. 'That's when I began to put on the brakes on the project,' Mr. Thompson said in a recent interview at the museum ….'"
This has become part of the standard narrative of the dispute. See, e.g., Time's Richard Lacayo ("Joseph Thompson, the MASS MoCA director, says he finally called it quits when Buchel went back to Europe last December and left behind a list of new elements he needed for the installation, including the fuselage of a large jet liner ....").
But here's Joe Thompson in September 2006, in an email to Christoph:
From: Joe Thompson
Date: 16. September 2006 00:13:53 GMT+01:00
Subject: Big thoughts, key information
Only big things we haven’t really nailed down yet are the house, and the big airplane fuselage. Nato is hauling a ton of useful junk in every day, and Richard has found great bar stools, and related materials. Going pretty well on that front, and we’re just getting started.
I’m terrified about the costs, by the way. So far, we have zero in sponsorships, nada,…if you have any ideas for that, let me know, as I really have to get to work on that right away.
"Final straw," huh?