The Rugby Football League has confirmed that the trio, who played for Pia in the earlier rounds of the competition, before being knocked out by Keighley, are not cup-tied, as Pia are not a member club of the RFL.
Kahler, Youngquest and Franze all scored tries in their debut match against Whitehaven last weekend, and have all signed 18 month contracts with Thunder, having joined the club following the conclusion of the French league season.
Chief Executive Rod Findlay said: “Paul, Nick and Kris were signed with a view to giving the squad a boost in the league as Thunder entered the ‘business end’ of the season. When we signed the players in January we didn’t know that we would have such a massive home game as St Helens in the Quarter Finals of the Challenge Cup. However, it is a real bonus that the trio can each play in this tie. If they can repeat their try scoring in this tie, Thunder might yet spring a surprise.
“This is a tie for everyone at Thunder – fans, staff, Directors, coaches, players and volunteers – to enjoy and I am sure there will be real competition amongst the players to make the 17 man squad. I am sure that will be the same for Kris, Nick and Paul.”