Phase One tried very hard to get the Contax line. For months and months.
The problem lay with Kyocera and Zeiss. They are caught up in a contract pissing contest and neither side would back down.
Kyocero said, we're losing money and so we're out of here. Zeiss said, no you're not, we have a contract and you have to stick to it. Phase One said, we'll commit to buying X amount of cameras and lenses, let's keep the brand alive. Zeiss, said, we can't because we have a contract with Kyocera (notwishstanding the fact that that it was unilatterally abrogated).
So, not wanting to deminish its legal case, Zeiss cut off its nose to spite its face, so to speak, and now the Contax 645 line is effectively dead. To my knowledge, Phase One has since moved on to other alternatives.
By the way, the above is all simply conjecture on my part, not based on any first hand knowledge.
Michael