Salvageable! Check the soil, it might need to be repotted, especially if the soil is dry and/or compacted. Other than that, water roughly once a week and keep it in a sunny window.
You can also take a cutting and put it in a glass of water as backup. Make sure to get at least one node (the wider area in the stem, usually with a little nub of aerial root starting). Cuttings with leaves attached will have an easier time.
Absolutely not, it’s just a bit leggy. You can either cut the individual pieces and replant them in dirt and they should sprout roots after a while, or you may be able to put them in water for a while (this method takes longer). As long as there isn’t any rot anywhere
Not too late. Clip off the spindly bits. Two options: cut into a few sections, it turn in water until they root then replant. Or, cut it into sections where there is a node in each section. Lay the sections flat across the Silk with the node facing down. Water lightly - like with a spray bottle every day until the nodes root and leaf. You can put cinnamon on the cut ends which acts like a fungicide. It you can find root growth hormone I find it helps jumpstart the rooting.
Good luck!