Was Judas present when Jesus announced the New Covenant?

If Judas was dismissed before Christ initiated the New Covenant in Luke 22:19-20, why does verse 21 say “But the hand of him who is going to betray me is with mine on the table.”

Luke records the moment of the Last Supper this way:

Luke 22:14 When the hour had come, He reclined at the table, and the apostles with Him.
Luke 22:15 And He said to them, “I have earnestly desired to eat this Passover with you before I suffer;
Luke 22:16 for I say to you, I shall never again eat it until it is fulfilled in the kingdom of God.”
Luke 22:17 And when He had taken a cup and given thanks, He said, “Take this and share it among yourselves;
Luke 22:18 for I say to you, I will not drink of the fruit of the vine from now on until the kingdom of God comes.”
Luke 22:19 And when He had taken some bread and given thanks, He broke it and gave it to them, saying, “This is My body which is given for you; do this in remembrance of Me.”
Luke 22:20 And in the same way He took the cup after they had eaten, saying, “This cup which is poured out for you is the new covenant in My blood.
Luke 22:21 “But behold, the hand of the one betraying Me is with Mine on the table.
Luke 22:22 “For indeed, the Son of Man is going as it has been determined; but woe to that man by whom He is betrayed!”

Luke's account covers the key details but doesn’t provide the exact sequence of events. In Matthew's Gospel we have a more precise account:

Matt. 26:20 Now when evening came, Jesus was reclining at the table with the twelve disciples.
Matt. 26:21 As they were eating, He said, “Truly I say to you that one of you will betray Me.”
Matt. 26:22 Being deeply grieved, they each one began to say to Him, “Surely not I, Lord?”
Matt. 26:23 And He answered, “He who dipped his hand with Me in the bowl is the one who will betray Me.
Matt. 26:24 “The Son of Man is to go, just as it is written of Him; but woe to that man by whom the Son of Man is betrayed! It would have been good for that man if he had not been born.”
Matt. 26:25 And Judas, who was betraying Him, said, “Surely it is not I, Rabbi?” Jesus said to him, “You have said it yourself.”
Matt. 26:26 While they were eating, Jesus took some bread, and after a blessing, He broke it and gave it to the disciples, and said, “Take, eat; this is My body.”
Matt. 26:27 And when He had taken a cup and given thanks, He gave it to them, saying, “Drink from it, all of you;
Matt. 26:28 for this is My blood of the covenant, which is poured out for many for forgiveness of sins.
Matt. 26:29 “But I say to you, I will not drink of this fruit of the vine from now on until that day when I drink it new with you in My Father’s kingdom.”

Mark’s Gospel confirms this sequence:

Mark 14:17 When it was evening He came with the twelve.
Mark 14:18 As they were reclining at the table and eating, Jesus said, “Truly I say to you that one of you will betray Me — one who is eating with Me.”
Mark 14:19 They began to be grieved and to say to Him one by one, “Surely not I?”
Mark 14:20 And He said to them, “It is one of the twelve, one who dips with Me in the bowl.
Mark 14:21 “For the Son of Man is to go just as it is written of Him; but woe to that man by whom the Son of Man is betrayed! It would have been good for that man if he had not been born.”
Mark 14:22 While they were eating, He took some bread, and after a blessing He broke it, and gave it to them, and said, “Take it; this is My body.”
Mark 14:23 And when He had taken a cup and given thanks, He gave it to them, and they all drank from it.
Mark 14:24 And He said to them, “This is My blood of the covenant, which is poured out for many.
Mark 14:25 “Truly I say to you, I will never again drink of the fruit of the vine until that day when I drink it new in the kingdom of God.”

Finally, John’s Gospel also shows the departure of Judas happened at the start of the evening in Chapter 13. So, Judas was dismissed prior to Jesus inaugurating the New Covenant ordinance with His true disciples.