Here is an article with some actual facts. For example, the Dolphins have 19 undrafted players on their roster and 15 players that were added to their roster after training camp began. In other words, it's not a roster with a lot of quality NFL talent.
https://www.miamiherald.com/sports/nfl/miami-dolphins/article235500782.html
And here's another, with lots of former Alabama players weighing in.
https://www.si.com/nfl/2018/11/23/can-alabama-beat-nfl-team-nick-saban-reggie-ragland-marcell-dareus-mark-ingram