Any progress? I have identical situation, in your problem and your steps to resolve. I'm thinking the partitions got nuked. Unfortunately, ADB won't recognize in Windows, and I don't have Adb installed in my Linux machine to manually repartition. I'm thinking partition 5 got wiped, which of what I read is a hard brick, as it contains all the device info.
Have you tried partitioning a sdcard with CM installed to run off of it? I believe this will be my next step..if that fails I'll try to repartition with Linux.
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