So I am back from my Eurodam Alaska Cruise (6/24 - 7/1). The Behind the Scenes Tour was not offered. I talked to guest services and they said it was stopped during COVID and has not started up again.
The "City on the Sea" show on the last full day of the cruise is closest you can get, and it is better than nothing. That being said, if you know any thing basic about how a cruise ship works, you aren't going to learn anything new.