Lo-Fi Games

I was watching someone on Twitch play on experimental and after they committed a crime even if they ran somewhere far out of sight the character could not sneak to get away. The character could still be seen through hills, buildings and walls. The person had to save and load and then the npc that could see them sneaking would no longer be able to see the character that had committed the crime and would no longer pursue. Is this a bug with committing a crime or sneaking?

You should only report bugs here but it's an AI gap, npcs don't know how to react to line of sight loss, the only thing they know is combat with that target or not. I'm sure devs know about this, hopefully they'll come up with something.
As for not being able to stealth, it's because you are in combat and the stealth stance gets automatically removed for your own safety as characters can't react to combat in stealth.