I would not put it in water; I suggest you get some new potting soil asap, a pot with drainage holes that is big enough to house what roots there are on the bottom of the one stem that appears to still have life in it without cramping or bending the roots, and pot it up properly, making sure the roots are all buried properly, and planting it no deeper than it was originally,as it was before you did this with it. Water in thoroughly, letting excess water drain away freely, then stand somewhere with bright light or sunlight. Water again only if it starts growing and if/when the surface of the soil feels dry to the touch, and always empty any outer pot or tray afterwards so the plant is not left sitting in water.
You don't say where you are in the world, but when the weather warms up, if the plant survives, it will benefit from being outdoors as long as temperatures are reasonably high, particularly at night. It's impossible to tell from the first image whether spider mites or something else were present or not; some evidence of something is visible, but the colour of the picture makes it impossible to tell what - what precisely did you do to get rid of the 'spider mites'? Regardless, spider mites are common on indoor plants because of overly dry and warm/hot air, so monitor the plant ongoing if it recovers to make sure they aren't a problem again. If you have other houseplants, check that they do not have spider mites too