I thought there was a rule in RROP which stated specifically that the seating draw must be seperate from the button draw, but I cannot find it. I did find these rules though that more or less say the same thing, in TOURNAMENTS:
2. Initial seating is determined by random draw or assignment. (For a one-table satellite event, cards to determine seating may be left faceup so the earlier entrants can pick their seat, since the button is assigned randomly.)
8. In all tournament games using a dealer button, the starting position of the button is determined by the players drawing for the high card.
We for the maority of Tournaments use the Seating Draw of the Tournament Software, followed by a high card for the button. In Regional or National Tournaments we do a single draw for the button, which is then used throughout the Tournament for all redraws, for example where seat 4 is assigned, that is then used throughout the tournament on all tables, FIDPA rules:
RULE 40 PLACEMENT OF DEALER BUTTON
In board playing / flop games, to determine the placement of the “dealer button” at the start of the tournament and after a re-draw of seats, cards will be dealt at a random single table, starting in seat 1. A single card will be dealt for each seat at the table. The high card dealt by “suit ranking” will determine the dealer button’s position. The awarded position of “dealer button” will then be used at all tournament tables.
Regards
Stuart