"The Speaker, having considered the matter, finds no question of privilege involved in the Deputy Prime Minister's responses," the spokesman said.
It is unusual for MPs to comment on privileges complaints once they have been lodged, but the spokesman said Mitchell had told media about the complaint.
"Mitchell went to the media before he even lodged the complaint, and on that basis I have no trouble with the world knowing he did not succeed."
Speaker Trevor Mallard declined to comment, saying that the Speaker never comments on privileges complaints.
The complaint centred on comments Peters made while speaking on behalf of the Prime Minister during Question Time on December 6.
"To the best of the Prime Minister's knowledge, the Minister of Police would have appraised her [the Prime Minister] of the fact that the police, on three occasions, had tried to ensure that there was protection if that was a concern, and the woman in question said that she did not want protection," Peters said.
"It would be very axiomatic that if on three occasions the police had offered protection and she hadn't availed herself of it, then maybe when the police came with the immigration officer, she wasn't under protection. It sort of follows like night follows day."
Mitchell said that Peters' response to the complaint was that he relied on information provided by the Police Minister.
"We know that the Deputy Prime Minister has misled the house because we know that information is not correct.
"We have asked the Police Minister to see the information that he provided to the Deputy Prime Minister and he has refused to release it."
He said it was the latest move by the Government to decline the release of information.
The Government has declined to name anyone who lobbied on Sroubek's behalf and Jacinda Ardern has also declined to release the contents of a text message she received from Richie Hardcore about Sroubek, citing privacy reasons.
Peters and National have verbally sparred in the House over the estranged wife, with National saying that Peters' comments have amounted to character assassination.
Peters also called her a National Party informant, which Mitchell said had exacerbated the woman's fears for her safety.
Mitchell said that the woman is not a National Party informant, is not a member of the National Party, and that she had contacted the Opposition after first seeking help from a former Labour Cabinet Minister.