varig8

Poor thing........What a mess!!.................IF you have spider mites on it, this is (maybe) the biggest problem out of all you mention. CUT each and every leaf off the larger plant. Be sure to cut the petiole as close to the stalk as possible. Take a paper towel soaked with IVORY soap and water and get down into the space as close as possible to wipe out any remaining spider mites. IF you leave the newest leaf on and it is still in the process of unfurling, make sure to wring out your towel with the ivory soap down into the middle of it to kill any mites hiding down there. DO NOT keep it near any other indoor plants that may also be infested with mites. Either that, or cut the mother plant down to the soil line and toss it. Thats what I would do. If the 'worm' you found is a banana corm borer, well, chances are he has already eaten tunnels through your corm which cuts off any distribution of water, food, etc., to the plant. It will die no matter what if this is the case. Whichever you decide, remove it from its pot, take it outside and hose off ALL the potting medium from the corm and roots.
If you have a mold or, more likely, a fungus, you'll have to dip it in a fungicide. Repot it in PROFESSIONAL POTTING MIX, not earth or dirt. This you can purchase at most garden centers. It contains peat, perlite, etc. This will allow for good drainage, aeration to the roots, and will not cake up like cement as dirt and earth would do. When re-potting corms like this, water once thoroughly when you are finished potting, then water only when its almost completely dry. It is much better to have them on the dry side than to have the roots rot when its too wet, which they will do. If it were me, Id just take the safest and easiest route out. Throw away the mother and remove the small sucker and re-pot it in the mix above, treat all the leaves with the Ivory soap, and just to be on the safe side, dip it in a fungicide. Since its winter, and probably the worst time of year to be doing this, don't bother giving it any ferts or coffee grains, etc. Again, easy on the water, do NOT keep it continuously wet! Once it starts to establish itself and produces new leaves, (probably spring) then you can water with fertz or coffee or whatever you like!

I had another look at your photos, and ya know what? You COULD cut the mother plant down to the top of the corm, cut off all the roots, dip it in a fungicide, and then re-pot it separately in another pot. This way IF it wasnt damage due to a corm borer, and it starts to grow again, you'll have 2!