The prop was sent to the sin bin for bringing Cowboys second-rower Luciano Leilua down in an awkward position just before half-time at Townsville's Queensland Country Bank Stadium on Saturday.
The hip-drop tackle can cause serious lower-leg injuries but, after standing up gingerly, Leilua managed to play out the game.
Already down 30-0, the Tigers conceded two more tries in Twal's absence to fall to the biggest half-time deficit of the season: 42-0.
On Sunday morning, the match review committee charged Twal with grade two dangerous contact and proposed a one-match ban.
Twal's suspension will be increased to two matches if he unsuccessfully pleads his case at the NRL judiciary.
As it stands, he will miss Thursday's clash against third-placed Cronulla.
Twal's teammate Isaiah Papali'i has been handed a $3000 fine for a hip-drop tackle of his own on Griffin Neame that went unpenalised on-field, while Jake Simpkin's dangerous throw on Neame will cost him $2500.Â
Both incidents were categorised as grade-one offences.
Canberra forward Emre Guler has been fined $1000 for a grade-one crusher tackle on Jojo Fifita in the Raiders' 26-22 defeat of Gold Coast.
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