From what I read, Upper Deck and Topps have a good reputation as far as putting real game worn jersey bits. But mistakes have happened, i.e. wrong color jersey that couldn't have belonged to the player on the card. Card companies send wishlists to teams in the offseason, i.e. please send game used jerseys for all these players, kthx. So they're at the mercy of the teams' equipment managers in a sense - these guys could be sending them anything, I suppose.
There's also a trend towards manufactured patches in recent years, but those are clearly indicafed on the back of the card.
Either way these 1-color patch cards have little value in general, unless they're rookie auto patches for a superstar.