New tools , YES! ;-) and the dvom is something you can use on all kinds of things, not just vehicles. And with the equinox happening you'll have a fully charged batt. in no time.
I doubt that the switch closed by itself.
I doubt the clutch depressed w/o the key on has any ( ? , sec. sys, tho ) effect on the electrical system.. ( and IMHO you most likely caused rust more with the plate off the flywheel ) that's neither here nor there in so far as your dead battery goes....... BUT because the two pedals are next to each other and you had some kind of device holding the clutch down my guess is that is involved with the dead batt. Either you pushed the brake pedal and the switch stuck or the device you had holding the clutch in also was pushing the brake and that switch closed.
I thought I had the 'radio code thing ' procedure stored for posting to ppl in here but I couldn't find that this morning , but if your operators manual doesn't have it ask in here and someone will. It is very simple IIRC. Ask about their charges for checking the battery before they do it and the clutch depressed routine sounds to me likey the cause of the battery going dead so your batt. is probably fine.
The electronics in the keep alive / security circuits are very low wattage devices and the solar charger should have been able to to keep up with that drain locked or unlocked....but yes , why not lock it anyway.
yw . Great , I'm happy to help if I can - and it's always nice to hear outcomes. Some post here with question / problems and get replies and you never hear from them again, so the ' ass u me ' thinking happens to the responders ( with them knowing ,LOL , their cure was the fix ) ..
Sometimes the problem is fixed and posters say thanks but don't indicate which suggestion worked.. :-o older vw van - O 2 light - speedometer cable reset location - either on the back of the speedometer or on the cable under the hood. - lol - dpluta - that paragraph was not directed at you , just me getting a laff. I'm easily entertained.