1) The 106th Congress spanned January of 1999 to December of 2000. The trip was made in August of 1999, during the first session of the 106th Congress. Now, perhaps it is true that Schaffer didn't plan on doing any work on any legislation or participate in any congressional activities for oh, 16 months, but I doubt it.
2) There is a direct link to Abramoff. Abramoff lobbied for the Mariana Island business interests that Schaffer visited. Abramoff's firm paid for the trip. How much more direct a link can there be?
3) Again, he was leaving Congress 16 months after the trip and had plenty of time to act on matters pertaining to the Mariana Islands during those 16 months, particularly considering that he sat on the very committee that handled issues relating to the islands.
4) The source is the Denver Post and I've already provided some linkage. Here you are again for the Mariana trip:
http://www.denverpost.com/news/ci_8872607
And for his bone-headed statement that got the ball rolling:
http://www.denverpost.com/breakingnews/ci_8834138