The following post was mostly written on the train there and back, with some updates after I uploaded the photos and had some time to add them in.
So, after I made it onto the Empire Builder (in spite of my best efforts), the actual trip to Williston went fairly smoothly.
Now, as I wrote in the original post, I booked a coach trip in both directions. The cost of buying a sleeper, even the cheaper Roomette, is more than three times the price, and more than on Anna's gift card. But, during the pandemic, Amtrak introduced something called BidUp. In order to encourage more riders to book sleeper rooms that would otherwise go empty, they invited coach passengers to submit a "bid" for a roomette or a sleeper, and it could be lower than the regular price. At the height of the pandemic, takes abounded of Amtrak travels being able to submit double-digit bids (the catch is that the bid comes on top of what you already paid for a coach ticket, so it's not quite as much of a bargain as it may seem, but still - savings!)
As the pandemic subsided, pulling off that trick got harder. But when I went to Meadville, Pennsylvania last May, the bid worked. I tried again this time for the Chicago-to-Willison trip, not expecting to get anything – especially since I set the bid even lower. But, to my surprise, it worked.
The trick seems to be to use it when booking tickets for less traveled destinations.
Now, around this time last year, I had a full-time job and enough money that I didn't have to second-guess it too much. In retrospect, I probably shouldn't have done it in the first place. I had the money - I still have savings - but it was not the wisest way to spend them. But what's done is done - and I consoled myself that, thanks to the Double Points promotion currently in effect, this will translate into quite a few Amtrak points, which would put me so much closer to having enough Amtrak points to pay for a Chicago-New York or Chicago-Washington D.C. round trip (I currently have enough points to go one way, but not quite enough to go back).
( The Sleeper Car experience )