"Potentially [they could be ruled out]. We fly tomorrow so [a decision] will have to be made before we get on the plane.
"They'll have to be quick. We'll see how they get through tonight and pull up."
However, Kearney was more optimistic about five-eighth Blake Green's chances of returning from a rib cartilage injury suffered in the dying stages of the win over Brisbane a fortnight ago.
The 31-year-old was struggling to pass the ball at training last week before being ruled out of the match against the Storm but has made good progress in his recovery over the last few days.
Back-rower Leivaha Pulu has been named in the extended reserves for his first NRL match since overcoming a foot injury and could be promoted to the starting side if Harris is ruled out.
"[Green] is probably a bit further ahead than [Luke and Harris]. He's pulled up pretty good," said Kearney.
"[Pulu] is good. He played 60 minutes for the ISP team on Sunday afternoon so he's good to go."
Green will also have his injury assessed further by the club's medical staff tomorrow but was bullish about his prospects of playing after completing an intense 90 minute session.
"I'm all good. I'm ready to go this week," said Green.
"It healed up pretty quick. I'm pretty lucky that it's all settled down so I'm ready to go.
"I'm looking forward to getting over there and spending a few days in camp together so it should be a good time for us to re-group."
Green revealed the eighth-placed Warriors have targeted the next two matches as crucial to their hopes of making their first finals appearance since 2011.
After facing the 12th-ranked Titans they will remain in Australia to prepare for next week's tough assignment against the second-ranked Dragons at WIN Stadium in Wollongong.
"We've got two weeks on the road, we're staying over in Australia after the weekend's game, we're not coming back," he said.
"So it's just about spending some time together and putting all of our energy into the next two week little block that we've got away and then we'll reassess after that.
"It's just important that we come up with our best performance. We've been fairly consistent besides that slip up against Penrith a few weeks ago I think we've put some good performances together.
"So we just need to keep improving and keep learning."
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