hey there Frosty, so about the leafs being eaten, sometimes when you buy soil that is not "horticulture standard" or not sterilized by steam , then it will contain some eggs from bugs or whatever, and they are "dormant", but when you add water and a good environment they will hatch. sometimes it's white flies which can be a problem because they lay eggs again and stay. but in your case it looks like may even a grass hopper, so he woke up, ate some food, then disappeared out of the tent i hope. If you have a big bud problem try to follow a more strict wet dry cycle and add bacilus thuriengiensis . For the rusty spots on the other plant , that is calcium deficiency. this can happen if you have some kind of wrong pH ... try to cut out fish mix, this often messes up the pH. Hope this helps ! 🚀