I think it's mindleboggling to assume Bowden didn't exactly know what Larkin's terms for a trade were.
Bowden was trying to shop a 10/5 guy that could block a trade.
It was well documented that Allen and Bowden had several conversations with Lark before the Mets trade. I'm sure since Bowden + Allen wanted to dump Lark really badly, that they knew EXACTLY what Larkin wanted (a multiyear deal).
Bowden lied to the Mets. Pure and simple. The Mets just wanted a rental.. Bowden knew Lark wouldn't accept a rental but tried to work it anyway.
Bowden did tell Phillips he thought Lark was a lock to accept the trade to get out of the "atmosphere of negativity" in Cincy.
Bowden gambled, and ended up looking like a fool.
And the circumstances of the trade don't change the fact that Bowden was harping for years how he wanted Lark to retire as a Red, but in reality the plan was to dump Larkin the whole time.
You don't have to like Larkin, but you are pretty naive if you believe it was a huge misunderstanding. The GMs just said that after the fact to avoid looking stupid. You can bet Bowden knew which teams Larkin would go to and what his terms were. Bowden is a liar, but not an idiot.