The moist soil is likely the culprit for any health issues your plant is having. Or, more specifically, the damage such can do to roots when the condition is prolonged, without a chance for the roots to reach some air as well as moisture. A soil that is composed of mostly fine particles, like peat, can often be what is causing the difficulty. If the roots are healthy, or can be rehabilitated, and the light is sufficient, there's no reason not to expect your plant to recover its' health, assuming it doesn't have some kind of virus or fungus.
Indirect east light doesn't sound like enough. Your tree would do much better with some direct light
When soil dries quickly (because it does not retain excess water, not just because it's too packed full of roots,) that is what is healthy for almost any house plants. Sitting in soggy soil is an unnatural state that usually/often causes roots to rot. When that happens, the roots are unable to deliver moisture and nutrients to the foliage. For a healthier plant, the soil should be chunky, porous, airy, not containing fine particles that behave like a sponge, holding water forever until they're suddenly completely dry and water just runs off.
It's usually recommended to wait until the days are longer, the rays are stronger to repot house plants, but I might do it pretty quick for this particular plant because I suspect it may be unable to regain its' health in the current conditions. If you'd like to wait to repot, when it does finally dry out, take it to a sink or shower and gently flood it with water, flushing the entire surface and contents thoroughly, then make sure it is finished dripping before putting the pot back on the drip saucer.
Leaving water sitting in the drip tray is something to which roots will have adverse reactions. Add some water chemicals, which can stay in the pot for extended periods if it's not drying quickly and being flushed once in a while, and you end up with a sick plant.
