I agree. The argument that Daniel and the other Hebrews were totally unknown to the King during their 3 year education does not match with the fact that court official was in fear of the King if he found out that the 3 Hebrews were not eating of the King's delicacies. The King must have 'checked up' on the boys during their education and during year 2 Daniel gave the interpretation.
If we really do follow the scriptures at their word, their was a deportation in 605 B.C.E. (using 'secular' chronology) under Nebuchadrezzar's first year as King and that is when Daniel was brought to Babylon. Otherwise, Daniel would be saying things he did not mean. If this 'second year' was after the destruction of the temple why didn't Daniel say so or why did he not say it was in the King's 20th year?
Here is an interesting chart (not that I endorse the whole site):
http://www.swartzentrover.com/cotor/bible/Timelines/690-570%20BC.htm