I am trying to just get Explore to return the timestamp that Satisfaction was offered at. I feel like this should work: 
But the problem is, it is ignoring a ton of tickets that match. In the image below, there's like, 100s more rows like the last ones, which I included to show it's finding the timestamp and working for some tickets. But as you can see, there's 2000 tickets where the field satisfaction_score was set to "offered", that do not have any timestamp listed. If I look at the tickets, there's a very clear and normal update offering satisfaction on them. 
Do I need to adjust my formula? Why is this happening?
It's Salim from the Zendesk Technical Team, this seems odd, maybe a filter or special configuration in the query is blocking these result I will create a ticket on your behalf, and we will check this together.
Best,