With the club set to head to South Australia for Gather Round, Dew admitted that Witts had been struggling with soreness and remained in doubt to feature.
"It's one of those things that's hard to put a timeline on," Dew said.
"He's been a bit sore all year and it's just managing that.
"Some games he's felt really good, and other games he's worked really hard to get through.
"We were just trying to get a bit of a circuit-breaker last week, give him that week off and see what impact that had on him.
"We anticipate when we bring him back in, he's at a really good level and not as sore as he has been.
"We know it's a long year … we won't risk him."
Ned Moyle performed admirably in his AFL debut and looks set to remain in the side should Witts' absence continue, while Dew admitted that the Suns could make some changes with Brandon Ellis looking likely to return from a calf injury.
The Suns head into their Gather Round clash against Fremantle with a 1-3 record, with another loss set to be a blow to their 2023 aspirations. The 53-point loss to St Kilda saw the Suns struggle to contain the Saints' momentum in the second half, with Dew admitting the side has plenty to work on.
"There's a number of different ways, whether that's contest, can we defend in a different shape, can we take care of the ball better?" Dew said.
"I felt like last week we really did invite pressure at different times. We can make better decisions with ball in hand, too."
Gold Coast will take on Fremantle on Friday, April 14 at 5:10pm, the first game in a Gather Round doubleheader.