It's in Romanian, because this is the league I follow, but something like this [1], maybe Google Translate can help, basically a player (incidentally, playing for the team I follow) letting in a goal just because (the goal on YT in here [2]). Maybe that was still because of a genuine mistake, but searching for "pariuri site:https://liga2.prosport.ro/" returns many other articles related to suspected betting in the Romanian second league.
Also, at a (much) higher level club owners like Napoli's De Laurentiis might be crazy enough (I do personally see him capable of that) to be directly involved in this sort of stuff.
There was a very suspect thing happening at the end of last season in Italy, basically Napoli needed a (relatively easy) home win in the last stage against a smaller opponent which had nothing to gain anymore, but they didn't, the match ended 1-1 [3], so Juventus (one of Napoli's biggest rivals) got their CL place instead. As a Juventus fan I saw that as very, very suspicious, especially as I could have sort of guessed beforehand that that sort of thing would happen.
And before anyones says: "no Serie A club owner would do such a highly illegal thing!" a couple of months ago Sampdoria's (now former) club owner got arrested because of some other illegal shenanigans (afaik not betting-related)
[1] https://liga2.prosport.ro/cupa-romaniei/se-va-sesiza-comisia...
oh muh gawd! i've done that very thing myself. i didn't know i could make money doing it.