Hi, did you recently get that guy from an ebay auction or a classified here on OB? I got a couple of epigeneium seedlings from a seller here on the board. each of mine lost a leaf (or two) after shipping and adjusting to their new environment. Epigeneiums do loose their old leaves and eventually the old bulbs will turn yellow and shrivel...
anyway, i have a couple blooming size Nakaharais and they loose old leaves from time to time. Nonetheless, my seedlings seem to have stablized and one of them is even putting out new growths
I wouldnt worry about it. Give your guy some time. they are slow growers, but with the conditions you described it should do well...