Harmonic Balancer/Crank Pulley/Timing Belt(?)

Basics first then detailed account. Please and thank you for your help.

Key points; Drive shaft pulley/harmonic balancer bolt was backed out fully and removal of pulley was as simple as grabbing it. No longer attached in any way.
--No warnings
--Pulley bolt and full pulley assembly came right out. Bolt not broken or stripped
--The vehicle still cranks.
--No noticeable damage outside of the specific problem.
--**There is a fairly deep gouge in the inner wall of the engine side of the pulley. Like where it slips over the little nub that comes out of the crankshaft.

?Right after this I am picking up a new pulley assembly and going to throw it on. This won't take but a minute sense all plastic, tire, old pulley, is out of the way. Torque belt to spec (210?)
--Should I be concerned about timing belt?
--What is likely the culprit?
--What should I be looking for while re-installing new pulley?

No real noticeable signs of oncoming problems. Pulled off the Interstate, as I turned left after a stop heard a very noticeable bang and lost power steering and some electrical function but still had lights. Obvious belt slip in my mind at the time. Upon stopping at drive through engine stalled, still had electric. Started right back up, I pulled out of line and parked it. Got some food and ate it before opening the hood. (The hunger grumps are very detrimental to rational decision making) Yup belt was loose, just kinda off center on two topmost pulleys and kinda jammed between tensioner pulley and it's arm. So, being 1am and literally 3/4's a mile from home I got the belt outta the way and drove er to wear she now sits without issue.

Trying to be detailed but I think the rest is pretty straight forward. Next day got a new belt and went about the ten minute job I mistakenly assumed was all that was needed. Crankshaft pulley/H. Balancer was loose so I reached down to tighten the bolt. (At the time not understanding that this isn't a simple tighten and go fix). So the bolt came right out with half turn and the entire pulley/balancer came with it. Came up to do research and have noticed most instructions on working with that pulley involve it being dificult to pull off. Now, after a few more hours of reading has gotten me nowhere I succumb to my lack of knowledge.