Samoa began with a big bonus-point win over Russia in their opener, but they were later hit by three-match bans for centre Lee-Lo and hooker Matu'u.
Both players had been sent to the sin bin for dangerous tackles before seeing their punishments upgraded to red cards in subsequent hearings.
Coach Jackson said: "Both cases we thought were dealt with on-field. They obviously didn't go there intending to make contact anywhere above from where the ball is."
He added: "Do we accept the sanction? Yes, we do. Do we agree with it? No, we don't."