I personally definitely think all three of Sifa, Moylan and Wilton need to improve their defence, and all contribute to making it harder for each other.
The problem flows from Wilton out - I kind of blame him the most as the 2rf is supposed to set the edge and the outside men work off of him.
However he is also the most junior of the players, so I certainly don't blame him alone. Actually blame is probably the wrong word all together, however if I could pick any one of the three to drastically improve their defence it'd be him. I think that would then flow on the benefit the other two.
Wilton can be drawn in and can also be indecisive, additionally he is not the strongest defender and I don't think his on the line D communication is great (an assumption). This is mostly youth and inexperience I expect.
Moylan then also becomes indecisive and when out of position seems to opt to play touch instead of at least trying. Even though he won't make many 1v1 stops on the line I think we'd all appreciate a bit more effort.
Then Talakai has Moylan who won't/can't make 1v1s who might need his help but lacks the lateral movement to adjust in or out after he hedges his bets, so he gets stood up out of position.
To be fair also while this does need to be fixed up a bit it's not like no other side in the NRL has leaked any points. A well worked 3v2 created and executed will be the 'cause' of the try more often than any one two or three of these guys personal defence. No person or edge in the NRL has perfect defence. When you factor in a well created 3v2 often comes off a won ruck it is evidently more than just a 3 man problem, but that doesn't mean they have no responsibility to get better.
We don't watch our own backline shred opposition and thing 'oh lucky they have weak tryline defenders', we credit our good work to create and execute.
Another factor in our edge tryline defence is Kennedy often trails the play along the line. Some fullbacks trail to cover kicks, offloads and angle changes. Some fullbacks push hard outwards and are more likely to get to a point where they assist with a tackle on an in to out string of passes, but they can't assist if anything else happens as they overrun it. I couldn't tell you which is more effective. It's possible Kennedy could get better at reading which to do when, although it would be tough to make those calls on the fly, especially against good halves.
Probably other factors too I haven't thought to mention or am not even aware to look for. It's a team game, individuals can improve to help the team but the team can improve to help the individuals too.
tldr; yes, Talakai and Moylan need to work on their defence
