Super League chief executive Robert Elstone says an agreement has been reached with Betfred - one of the UK's biggest betting companies. Gambling is considered 'haram' or forbidden in Islam, along with other practices like drinking alcohol.
Williams converted from Christianity to Islam in 2009 and was the first Muslim to play for the All Blacks.
"I think the matter has been resolved in satisfactory fashion," said Elstone. "I have say a big 'thank you' to Betfred for the way they've managed this.
"We suspected it might be an issue, but it only really surfaced five or six days ago, and Betfred have taken it on, considered it and come up with the right answer, and one that works for all parties.
"I'm really pleased they showed a progressive, pragmatic approach to this."
Last year, the Super League extended its sponsorship deal with Betfred for a further two seasons, worth an estimated £1m (NZ$1.98m) a year.
But that figure is nothing compared to Williams' contract, reportedly worth £5m (NZ$10m) over two years.
Williams has refused to wear a sponsor's logo on a jersey before. In 2017, Williams covered up the Bank of New Zealand logo on his Blues top, with permission from NZ Rugby.
He taped over the bank's logo on his collar in his debut and a new jersey was soon created, sporting a Plunket logo in its place.
Meanwhile, Wolfpack chairman Bob Hunter has confirmed the dual-code international has given equity in the club.
"He was offered, as part of his package, a significant number of shares in the parent organisation and the intent long term is to take that whole company public," Hunter said.
"You don't know whether that's worth a dollar a share or $10 a share. The market, at some point, will tell you what they think it's worth, but it's significant."
Williams missed the Wolfpack's lone pre-season game earlier this week, but is set to feature in their season-opener on February 2 against the Castleford Tigers.
In mid-February, he will then return to New Zealand for the birth of his fourth child.