Not long after Jesus’s arrest, Judas Iscariot died (Matt. 27:5; Ac. 1:18), leaving eleven apostles.
In Lk. 24:33–35, the two disciples from Emmaus, Cleopas and Simon, return to Jerusalem and find “the Eleven” gathered together. Luke’s use of “the Eleven” is a title for the group, just as “the Twelve” remains a title even after Judas’s death (cf. Jn. 20:24). It does not require that all eleven were physically present at every moment. Luke’s point is simply that they returned to the apostolic circle and reported what had happened.
The next scene — Lk. 24:36-43 — corresponds to Jn. 20:19-25. This is a later moment, when Jesus appears to the gathered apostles for the first time after His resurrection. John explicitly notes that Thomas was not present during this appearance. That is why only ten apostles are physically there, even though the group is still referred to collectively as “the Eleven".
Then in Jn. 20:26-29, eight days later, the apostles are gathered again — this time with Thomas present — and Jesus appears to them a second time.
So the passages fit together naturally:
Luke 24:33-35: The Emmaus disciples return to the apostolic group (“the eleven”).
Luke 24:36-43;John 20:19-25: Jesus appears to the apostles; Thomas is absent (ten present).
John 20:26-29: Jesus appears again eight days later; Thomas is present (eleven present).
John 20:24 ~ After the death of Judas the betrayer, whenever the N/T speaks of "the twelve", that phrase includes Matthias who replaced Judas. This is evident in Acts 6:2 where "the twelve" called the multitude of the disciples to speak to them: at this point in the narrative Paul wasn't anywhere in the picture, so "the twelve" surely includes Matthias. After the John 20:24 statement the original twelve are not referred to anywhere else in the N/T, even 1Cor 15:5 employs the phrase and cannot be speaking of the original twelve because Judas was already dead, so it necessarily means the twelve including Matthias.
John 20:24 KJV
24 But Thomas, one of the twelve, called Didymus, was not with them when Jesus came.
This instance is speaking of the original twelve, so you would be correct, Judas wasn't there and therefore there were only ten original apostles present. I've already made that point: it is already a fairly large part of my argument, (the redactors did not mention the number ten for rather obvious reasons, as explained, (the error would be too obvious)).
Luke 24:33 ~ It says what it says, "the eleven", and there is no way around it, and this is the companion passage to John 20:24 where there were only ten apostles present according to the erroneous text handed down through church censors, redactors, editors, and twisters.
Luke 24:33-34 KJV
33 And they rose up the same hour, and returned to Jerusalem, and found the eleven gathered together, and them that were with them,
34 Saying, The Lord is risen indeed, and hath appeared to Simon.
These two passages are no doubt companion passages speaking of the same occasion:
Luke 24:33-40 KJV
33 And they rose up the same hour, and returned to Jerusalem, and found the eleven gathered together, and them that were with them,
34 Saying, The Lord is risen indeed, and hath appeared to Simon.
35 And they told what things were done in the way, and how he was known of them in breaking of bread.
36 And as they thus spake,
Jesus himself stood in the midst of them, and saith unto them, Peace be unto you.
37 But they were terrified and affrighted, and supposed that they had seen a spirit.
38 And he said unto them, Why are ye troubled? and why do thoughts arise in your hearts?
39 Behold my hands and my feet, that it is I myself: handle me, and see; for a spirit hath not flesh and bones, as ye see me have.
40
And when he had thus spoken, he shewed them his hands and his feet.
41 And while they yet believed not for joy, and wondered, he said unto them, Have ye here any meat?
42 And they gave him a piece of a broiled fish, and of an honeycomb.
43 And he took it, and did eat before them.
44 And he said unto them, These are the words which I spake unto you, while I was yet with you, that all things must be fulfilled, which were written in the law of Moses, and in the prophets, and in the psalms, concerning me.
45
Then opened he their understanding, that they might understand the scriptures, [John 20:22]
John 20:19-24 KJV
19 Then the same day at evening, being the first day of the week, when the doors were shut where the disciples were assembled for fear of the Jews,
came Jesus and stood in the midst, and saith unto them, Peace be unto you.
20
And when he had so said, he shewed unto them his hands and his side. Then were the disciples glad, when they saw the Lord.
21 Then said Jesus to them again, Peace be unto you: as my Father hath sent me, even so send I you.
22 And when he had said this,
he breathed on them, and saith unto them, Receive ye the Holy Ghost: [Luke 24:45]
23 Whose soever sins ye remit, they are remitted unto them; and whose soever sins ye retain, they are retained.
24 But Thomas, one of the twelve, called Didymus, was not with them when Jesus came.
Luke has the eleven remaining apostles present, but John has only ten remaining apostles present, and the most likely answer for this error has already been offered in the sum of this thread: the answer simply isn't acceptable for the indoctrinated mind.