In early June (1875), rumors were afloat that a game between the Boston Red Stockings and the St. Louis Brown Stockings had been fixed. Boston won the game 15-2, and gossip hinted that St. Louis shortstop Dickey Pearce "had received money from a prominent merchant to keep himself out of the way of ground balls."
-Daniel Ginsburg, The Fix Is In: A History of Baseball Gambling and Game Fixing Scandals
Well, there you go. During their entire existence and at least once a season, members of the St. Louis Brown Stockings were accused of game fixing. I think Ginsburg's source is the Eagle but I'll have to run it down.
I'm not prepared to state that the Brown Stockings were a corrupt club from head to toe and beginning to end but we have lots and lots of smoke here. Pearce, McGeary, Battin, Blong, Force, and McManus were all accused of game fixing to one extent or another between 1875 and 1877. There were subtle accusations against Bradley during the McGeary incident in 1876. Were all of these accusations creditable? No. But some were. Throw in problems with the umpires that the club employed and rumors that cropped up among the fans from time to time that the team was laying down and it's one big ugly mess.
Now given the times, it's possible that this was something that all clubs went through. I don't know if that's true but there were a lot of accusations flying around and not all of them were true. So it's possible that there were several clubs during the 1875-1877 period who's players were habitually accused of game fixing. If so, we can add the Brown Stockings to the list and move on. If not...
And completely off topic, did you know that Oliver Hardy never said "another fine mess" in a film? He always said "another nice mess." You learn something new everyday.