Thanks for everyone's feedback! This was helpful. Your suggestions have prompted me to think about alternative options, especially considering how difficult it would be to detach the conduit (I thought I just loosen the nut thingies, but looks like that's not the case). I figured there's no way to replace or expand the current switch box, so I'll find a way to just add a second one alongside it and use two separate switch plate covers. After opening the wall more, it seems there's just a board running between the two studs (see pic) that the current box is nailed to. I plan to get another box that's the same depth and just screw it to the same board. Punch the holes between the two boxes, connect wiring through there. Not sure how many electrical codes I'll be violating haha...

I bought one of these by mistake, not getting information from the Home Depot representative when I asked what, if anything, was different about this model from another that would be available. Since I have NEVER owned an oven that is not self-clean, I assumed that "Easy Clean" was just a gimmicky euphemism for "Self Clean!" Yes, I was at fault for not investigating further, but for me it would be like asking if a car was equipped with wiper blades! I am so upset by this, but glad to hear of some possible solutions to the situation, as I find the so called "Easy Clean" by LG totally useless!

Is there a hallway wall behind that ties into that stud? If so, not a good idea to remove the whole stud, maybe just remove a portion of it? And add blocking to tie it into the next stud to the right? What about moving the switch box farther into the room, as in attaching your 3 gang box to the stud to the right of your arrow? Or use a 2 gang box with dual switches to save space? https://www.homedepot.com/p/Leviton-Decora-15-Amp-Single-Pole-Dual-Switch-White-R62-05634-0WS/100356887

Maybe? Cut a larger round hole where the J box to give you better access? Patch with drywall and cover with a ceiling medallion? Or cut a small access hole directly in front of where the bracket is attached and use a right angle drill or drill attachment to remove the screws? Look like drywall screws holding it in the photo. Were the ones that you removed drywall screws? If so, they are brittle and snap easily. Manhandling it...grasp, twist, pull...lock onto the bar with vise grips...might get lucking and be able to snap the screws.