Not sure of the difference between 'being signed' and being in a squad, but Talakai is also in Souths Harold Matts squad.
I am also pretty sure that Ruthven & Longland played Harold Matts with Manly last year.
I suspect the reality is that barring a very small minority who are either at very traditional & strong rugby school (ie. Joeys) or a tall 2nd rower (whose height makes league less interested in them, but prime AFL candidate) that pretty much all the players are playing both games these days and view the games are interchangeable.
I could be wrong, but I am pretty sure that Xuerub's only rugby union during 2025 was playing for CCC, then NSW School 1 and Waratahs.