Zacchaeus was a rich man more than willing to give up his riches to follow Jesus.
As it is written and as a matter of fact, that didn't happen. Most probably after that Zacchaeus lived a 'contentment' life and collected tax from his people as only what required by the Romans. Repented Zacchaeus would have 'performed this, because this is in 'relation' to what John the Baptist said to the tax collectors who came to be baptized, written in Luke 3;12 and 13.
the rich man in mark was very excited about talking to Jesus, fell to his knees and claimed he had followed all the commandments. but Jesus asked this man to do one more thing, give up his riches. and at this the man said no more, he went away in despair because he had great wealth. the very thought of losing his riches put him in sadness. one would think eternal life and the majestic kingdom of our Lord would make someone very happy but thats not good enough to make some rich men give up all their wealth. and i think thats the point Jesus was making with the camel and needle.
i believe this rich man was proud and boastful of his wealth and religiousness, challenging and bragging even to CHRIST of his 'eligibility' to enter. When CHRIST who brought us Grace and Truth, put him to the test, and his 'countenance' fell and speechless.
But that man still have a chance to learn from Zacchaeus or anyone like him, about true repentance, and moreover this may have taken place, because it comes in 'relation' to JESUS's finishing word/teaching that and as it is written;
"For man somethings are impossible, but for GOD all things are possible."
GOD bless you all in the name of LORD JESUS CHRIST.
