The South Africa wicketkeeper-batter had earlier made himself unavailable ahead of their match against West Indies on his stand of taking a knee.
The Sri Lankan side is placed second in the Group 1 having won the lone game they played against Bangladesh.
While Cricket South Africa has issued a directive that the South Africa team must collectively take a knee pre-game prior to this match, De Kock had failed to do the same in their previous matches.
The South Africa wicketkeeper-batter had earlier made himself unavailable ahead of their match against West Indies on his stand of taking a knee.
The Sri Lankan side is placed second in the Group 1 having won the lone game they played against Bangladesh.
While Cricket South Africa has issued a directive that the South Africa team must collectively take a knee pre-game prior to this match, De Kock had failed to do the same in their previous matches.