Looks like fungal spots..just keep it dry for now. What are your temps now? If it continues to be humid, it can be left drier for awhile. It will eventually scar and you may lose the leaf or it may just heal itself. Jades are very tough. They easily bounce back.
Forgot to ask..is the plant in a container? You may want to position the plant in a sunnier area, south side is really good for them. More warmth.
