Please help. Lower alternator pivot bolt.
 

Ive scoured all corners of the internet. Read tons of posts, tried everyone's idea to get that bolt out. Previous owner had welded a 27mm nut onto the bolt head because he rounded it off, that weld broke free when trying to remove it. Now I'm stuck with a round bolt, ive tried the extractor sockets, soaked with tons of penetrating oil, busted plenty of knuckles, vise grips go on as tight as one could get them, and they just dig into the bolt and take more metal off of it. Ive hammered the alternator, ive pried it. Ive torched it to no end, the mani brace is already out, not much room. Am I left with the last option of just cutting it off? The alternator did move a bit with the 2lb sledge, but the bolt remained in place. Also, theres a hose that goes into the lower a arm on that side, is it necessary/what exactly is it?, its right in the way of getting to the pivot bolt

The right way is a 14mm socket, you're clearly past that.

Cut the front ear off the alternator, being careful to not cut into the oil pump. Once cut off and removed, you should be able to tap out the bolt and remove the alternator.

That hose is the vent for the charcoal canister.

Rip to my core charge lol. Any best option to cut with? Or just go to town with whatever tool will fit? Do you think maybe an oscillating multi tool with a carbide blade would do the trick considering it's just cast aluminum?

Unless the vaccine helped you grow a 3rd arm, I would suggest you have a friend hold a vacuum hose close, but safely, by to avoid or minimize sending metal shavings everywhere.Yes, any tool that is available and works. I would probably start with a Dremel, then a cutoff wheel, and lastly a sawzall in that order. Each should cut thru aluminum like it is warm butter. My buddy told me this afternoon that he burned down half his garage yesterday from some sort of fuel injection mishap. Be careful and safe that close to the fuel system.