Welcome to the forum.
can you remove more of the collection to put it in a vise?
Good socket from a quality source and an impact gun would probably bust it out.

 

These, anybody with a modern harley needs a set. They'll do torx's too.

 

I had a similar problem. I used a Torx that was close and hammered it in to get the bite and backed it out. No heat, no risk of damage to anything other than the intended target.

 

+1 those are a must

 

This ^

 

Get a better set of vice grips, there's plenty of meat to grab there.
Or a pipe wrench.
Are you turning it the right way? Only asking because I see you broke the shifter peg stud.

 

That bolt does not look damage beyond the start.
Is it possible that someone might have used a regular "L" allen/hex instead of one on a socket?
or maybe a ball end allen/hex?
Then tried to enter at an angle due to obstruction of floor board bracket or kick stand?
From a distance it looks like a correct size but short regular allen/hex socket can be tapped into the bolt.
If you do not have that readily available then just cut a piece off your allen/hex and put it in a socket.
Then use a rachet.

 

+1 I don't have this exact set but a similar set and it has saved me many times with old bikes that have been mistreated. I have had a few project bikes that others have left outside for years with many stripped or corroded bolts. They have also helped me with lots of other unrelated projects too, a must have for any workshop

 

take dremel or hacksaw, cut across head of bolt, and convert to slotted bolt. than use large screwdriver to extract.

 

Are you kidding us now? No offence but that's got to be the easiest bolt on the entire bike to get off even if stripped, wait till you strip the case for the oil plug.