If I remember correctly, there was some issues at the time and the players association was advising players not to sign with Topps for various reasons. If you remember, at the time the biggest example of that was Kevn McReynolds who did not have any Topps cards from 1984 until 1987 Topps Traded.
Here is a link to an old Net54 discussion
http://www.net54baseball.com/archive...?t-131821.html
And, today, Matt Wieters of the Baltimore Orioles never signed with Topps
Rich