Water damage and electricity

Hi, my friend spilled water from the side on my Macbook Pro and she turned it sideways to dry it off. The laptop was not completely turned off (on sleep). The next morning I plugged in and didn’t turn on. It’s been almost three days and it doesn’t seem to turn on. I have AppleCare+ but it said the warranty won’t cover any liquid damage. I’m trying to find ways to fix it without being so costly. I’ve seen videos that clean the hardware with alcohol and drying it off but I was wondering if that would work. My questions are:

1. Is red LSI indicator permanent after I spilled water? I’m afraid that Apple will reject whatever further damage due to the red indicator even if the damage is not from water.
2. Should I replace the battery? What sort of parts should I replace after this water damage? Or should I just clean the hardware?
3. Does anyone have similar story like me where they successfully restored it by DIY?

Thank you!