External Hard Drive Won't Mount I've searched and tried a lot of stuff but still can't get it to work.

I was able to use my seagate HDD properly last week but now it doesn't mount. I tried plugging it to a PC &amp; another mac, it works fine on both. The reasons could be 


Updating OS to macOS Sierra 
Not ejecting properly
Installed sims4 with wineskin


Things I have tried.


From disk utility clicking on mount &amp; first aid.

From terminal writing: diskutil mount disk2s1 &amp; diskutil mount readOnly disk2s1 both resulted with this 
Volume on disk2s1 failed to mount
If the volume is damaged, try the "readOnly" option
From terminal writing: diskutil repairDisk disk2s1 &amp; diskutil repairVolume disk2s1.
Restarted mac in normal mode &amp; safe mode.
/private/var/log/install.log from here found some logs but don't know what to do with them. 
Switch USB ports &amp; retry.
A couple of other things.
I'd recommend checking if fsck is holding your disk hostage upon connection. This was it for me.

Running ps aux | grep fsck revealed:

root              2587   7.3  0.1  4363584  21780   ??  U    10:56PM   2:22.54 /System/Library/Filesystems/exfat.fs/Contents/Resources/./fsck_exfat -y /dev/rdisk2s1

So the solution was a sudo kill -9 2587 (insert your PID instead of 2587) (or sudo pkill -f fsck).
As soon as that ran, my Volume immediately mounted.

Oh the irony of fsck being the problem...

Addendum (surfacing from comments):
Ideally, you're better off letting fsck run its course. Otherwise, you'll run into this the next time too.