I went to the match between Senegal and Colombia two days ago, which took place in Samara Arena. It was a really good experience, even if the match was somewhat lackluster during the first half. The stadium was full of screaming Colombia fans, the total number of people was 41,970. The second half brightened up considerably, with Colombia scoring a header goal. Rather a lot of yellow cards for the Senegalese though. Here is a BBC article about the match:

https://www.bbc.com/sport/football/44439305

As a data point, contrary to expectation I didn’t need my passport to get in, just the Fan ID and ticket.