When sublimating, it not only may not be a perfect match with your jersey, however, even from job to job when done at separate times.
The way you can tell a sublimated part is that the backside will be "white".
Unfortunately, sublimation is not an exact process, in many ways. For example, the sublimation that EPS will do won't match what we will do 100%. The many reasons for this may include temperature sublimated at, pressure used, dwell time, temperature and humidity of the space where sublimation transfer is taking place, temperature and humidity of the space where sublimation printing is taking place, just to name a few.
So, in your case, where you say "I sent in some unusually colored jerseys", it may not have been EPS as much as it was CCM/Reebok. I can tell you for a fact that we've found that CCM/Reebok manufactures product in colors that are close and not exact as the color call out from the league/team.
Anyhow, we can discuss sublimation in greater detail if you wish, however, just know that YMMV with sublimated plates.