Hi Mintrider,
I might be missing some context here, but since you claim you can boot into that Mint installation, I assume you don't need to chroot into it, you can do just the normal sudo or open folder on nemo or caja as administrator and then open and edit the files you need. chroot is meant (if I'm not mistaken) for when you can't boot into an OS or you're booting a different one and want to change root (hence the name) into a different installation.
If you're still having troubles making hibernation work I can recommend installing
uswsusp. Then (if this isn't automatically offered to you on install) you configure if by:
It's text mode only but it will give you the chance to easily select the swap and compressing hibernation data (highly recommended if you're using a SSD you want to spare unnecessary writes and it makes hibernation and resuming faster). It also automatically performs the
update-initramfs -u in the end. It might also (not sure!) automatically set the needed information on
/etc/initramfs-tools/conf.d/resume. If not, you can create it and give it the swap file info.
Please note I'm writing this out of memory for hibernation to a partition, not to a file but I'm assuming as long as you give it the file to use it will also work. It worked for me when I tried hibernating to a file but that was years ago.
My contents for the /etc/initramfs-tools/conf.d/resume file is:
RESUME=UUID=435987e0-2644-4781-96ff-9dfa2ad2fde0
Again, this is for a swap partition and not for a swap file.
There might be some valuable information here:
https://askubuntu.com/questions/6769/hi ... -swap-file
You might check and even need to configure GRUB for it to know where to resume from after a successful hibernation. This might be the thing you're looking for.
Cheers.