The first one is Czech and the second one seems to be Polish PKP,so I was almost right
You've never been to sleeper trains before?

sounds unusual.
I've been a lot of times many years ago. Checked Polish PKP sleeper wagons on their site.. doesn't look good, hopefully it's better in reality. The best sleeper train I had was Warsaw-Moscow something like 6-7 years ago: super modern and comfortable (but I guess it was Russian/Bielorussian line), with large modern showers and toilets, sofas that were transforming to comfortable beds.. was very cool and luxury way to go to Belarus/Russia (but obviously not available from Europe anymore).
By the way, there's an interesting sight in Poland related to sleeper trains: in Białowieża there's an old train station built under Emperor Nikolay II (or "Tsar Nicholas" ) that was transformed into restaurant with Russian cuisine and Tsars' sleeper wagons with restaured beds/tables that you can rent for a night. We've been there in two wagons for a couple of nights, incredible experience. If you'll have more time,I recommend to visit it (as well as restaurant,it looks like a minipalace, a lot of luxury dishes with caviar etc, "White" Russian romances playing as music).
If you're visiting only Krakow,then I highly recommend to visit: Krakow's museum under city market, Oświęcim/Auschwitz and Wieliczka salt mine. There's also another salt mine called Bochnia, more "wild" one where you can spend a night 250 m under earth, also interesting experience (I've been there recently,was great)