Luke will front the NRL judiciary on Tuesday night to fight a grade one dangerous throw charge on Williams which threatens the hooker's participation in Sunday's grand final showdown against Canterbury.
Williams said he would be willing to do 'anything I can do to help' his fellow Kiwi beat the charge and that may include giving evidence before the judiciary panel.
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"That's just footy. I hope he gets off," Williams said after his Roosters were beaten by Souths in Friday night's preliminary final.
Rabbitohs coach Michael Maguire confirmed on Sunday that Williams is likely to play some part in the judiciary process.
"That's what I am talking about with the processes of getting all the evidence and taking it to the case," he told Triple M on Sunday.
"We've seen it work the right way and we've got to go through the formalities and put our case together.
"He's (Luke) disappointed being in this situation but he believes in the system.
"I believe it will be fine. The facts are there."
Both grand final clubs have concerns over their hookers, with Canterbury skipper Michael Ennis in doubt with a foot injury.
Hoping the bro @issacluke_14 is free to play this week, nothing in it just a solid hit..
— Sonny Bill Williams (@SonnyBWilliams) September 27, 2014