I would also like to note your ignorance about WHO Jesus was talking to in these cases. They are NOT the same people.
In Luke 24 you have a couple of disciples and NOT any of the eleven (Judas Iscariot had not been replaced yet).
Luke 24:18 (AKJV/PCE)
(24:18) And the one of them, whose name was Cleopas, answering said unto him, Art thou only a stranger in Jerusalem, and hast not known the things which are come to pass there in these days?
Luke 24:33-35 (AKJV/PCE)
(24:33) And they rose up the same hour, and returned to Jerusalem, and found the eleven gathered together, and them that were with them, (24:34) Saying, The Lord is risen indeed, and hath appeared to Simon. (24:35) And they told what things [were done] in the way, and how he was known of them in breaking of bread.
So NONE of the 12 apostles were the ones that were told that they were "slow of heart to believe" in THAT case.