The slate was not put together by Roemer.
It was put together by Ross Little, Louisiana’s Republican National Committeeman.
Little is/was a Thompson supporter.
See http://ringsidepolitics.com/The-News/-Rumors/Republican-Caucuses-in-Louisiana/
Ok, I heard a rumor about that. It sounds like you have a better understanding of it. From what I understand, though, many of the typical state politicos decided to join the Thompson slate a while ago.