"Things have progressed but I wouldn't say [signing with Newcastle] is imminent that's for sure," said Sharrock.
"There's a fair bit of water still to go under the bridge."
Newcastle are eying Luke as a potential signing as they consider options to replace sidelined hooker Slade Griffin, who suffered his fourth season-ending knee injury in July.
The Knights also have young Kiwi dummyhalf Danny Levi on their books and may yet re-sign versatile forward Jamie Buhrer and one-game rookie No 9 Tom Starling.
Warriors CEO Cameron George said the ball was in Luke's court as they continue to wait for him to make a decision on his playing future.
After shelling out big bucks last year to sign Blake Green, Tohu Harris and Adam Blair and having re-signed captain Roger Tuivasa-Sheck for four more years at the start of the season, the Warriors have little money left in the kitty. St George Illawarra front-row recruit Leeson Ah Mau will also join the Warriors next year on a three-year contract as the club's only major new signing.
"We've made our best offer under the circumstances of our cap," said George.
"That offer is before Issac and his manager to review and whether they have been provided with a better option we haven't been advised.
"We haven't been told anything yet and that's where we are at."
The club was counting on Nathaniel Roache serving as Luke's deputy before taking the reins next season but back surgery meant he was sidelined all year.
Having made just 20 appearances since debuting in 2016 the Warriors would prefer Roache gained more experience next season alongside Luke, if he agrees to stay.
Bench utility Jazz Tevaga impressed this season filling in at loose forward but was a stop-gap measure at dummy-half when Luke was out injured.
The 23-year-old is also off-contract and in talks to re-sign and Simon Mannering's retirement could see him spend more time at lock behind Adam Blair.
