Den. Heterorarpum - please help

[TOMMYMIAMI]

Hi Guys
I am not quite sure what went wrong with my Heterocarpum. Got it in July from Hawaii, it was looking good, though new growths were weak, but lot of growths, lot of keikis, and the main cane was pretty strong and long. I did water like my other Dendros, and it was not even raining much these days, fertilizing the same like all my other orchids, from time to time seaweed. 3 days ago I did see some leaves started to turn yellow and fall, but i did think it is fine. Today when examined i did see, that the canes at the bottom turn to softy yellow horrible looking shrinking stage. I am not sure if it is dying, if it get over watered, or what has happened. I quickly took it out of the pot, and the root system was not soggy or wet at all except roots on the top. I decide to mount it, which I wanted to do from the beginning but when I got it it was so big I decided not to. Not sure if you can see from the pics whats the problem, I would welcome any suggestions or diagnose and treatment if still possible