He questioned how the woman, who worked for a Saudi family in Riyadh for five months until August, could have continued to be healthy and without infection with nails in her body.
He also said that it was hard to believe she could have passed through several airport metal detectors on her return from Riyadh with so many pieces of metal in her body.
"Even someone with just one coin in his pocket has to remove it when passing through the detector," Badah said.
Saudi government officials dealing with the case have raised the same issue, labelling Ariyawathi's account "difficult to believe."
A spokesman for the Saudi embassy in Colombo told Sri Lanka's Daily News on Wednesday that the maid could not have passed through airport security checkpoints in Riyadh and Colombo without the nails being detected.
Ariyawathi, 49, returned to Sri Lanka on August 21 complaining that she had been beaten and tortured by her employers, who she said had hammered the nails and pins into various parts of her body.
Surgeons at Sri Lanka's southern Kamburupitiya hospital last week removed 19 of the nails -- some two inches (five centimetres) long -- and a needle in a three-hour operation.
Ariyawathi told them her Saudi employer inflicted the injuries on her as a punishment for her inability to communicate with those in the household.
"She said her employer heated the nails and then hammered them into her body," hospital director Prabath Gajadeera told AFP. "The nails were in her arms, legs and forehead."
Gajadeera said the woman could not have driven the nails herself.
"It is clear someone else had to drive in the nails," he said. "We will in any case refer her to a psychiatrist for analysis before discharging her from hospital."
The labour attache at the Sri Lankan embassy in Riyadh, Nimal Ranawaka, said he was aware of the Saudi doubts but that the case remained under investigation.
Saudi Arabia's English-language Arab News called for the probe to completed as quickly as possible to avoid further damage to the kingdom's reputation.
"Clearly the story has to be thoroughly investigated. If her employers did this then they must be punished rigorously -- and be seen to be punished," the paper said in an editorial on Wednesday.
"But equally, if the women did this to herself, hoping to benefit financially from it, she must be punished.
"Immediate action is imperative. The longer the case drags on, the more that can damage the kingdom’s reputation," the paper added.
Around 500,000 Sri Lankans work in Saudi Arabia, part of a massive foreign workforce that constitutes around 30 percent of the total Saudi population of 27 million.
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