Dendrobium death and Hopeful Rebirth

So I bought my mum a beautiful pandemonium orchid last year and it was looking beautiful until 6 months ago. However recently it's decided to grow a kiki on one stem and that stem has since detached from the main plant the other stems are also detaching and yet they are still looking green. I've advised mum to look after the kiki but would like to know if there is anything we can do to try and reserect the main plant

 

Dendrobium not pandemonium....ooops here's a photo of its sorry state. Can we maybe somehow replant the stems or are they completely dead?