Conservative Senator Gerald Comeau said the audit will be "issued as is, as it was delivered to us, and we can't monkey around with that report." Comeau made the remarks in an interview airing Saturday on CBC Radio's The House.
Comeau is the chair of the smaller steering committee that will write a report based on the independent auditors' findings. Other committee members include Conservative Senator Carolyn Stewart Olsen, who was once Prime Minister Stephen Harper's press secretary, and Liberal Senator George Furey.
The steering committee, under then-chair David Tkachuk, was accused of "whitewashing" a similar report in May on Senator Mike Duffy's expense claims.
Comeau hopes to make Wallin's audit and the report public by Tuesday afternoon, but adds the Senate may have to be recalled to deal with it.
"It's one of those things that can be done. For example, it depends completely what's in the report, and right now I don't know what's in the report," Comeau told James Fitz-Morris, guest host of The House.
"But if it is, let's say, a hard-hitting report, for lack of a better word ... because the internal economy [committee] can only recommend up to a certain point, it may need the Senate itself to implement some possible remedies."
Senate Speaker Noel Kinsella was not available for comment. Spokeswoman Annie Joannette said he has made no decision on whether to recall the Senate.
Duffy repaid more than $90,000 in ineligible expenses using money given to him by Harper's former chief of staff, Nigel Wright. The RCMP has launched an investigation into the payment.
Tkachuk, who has since stepped down as chair of the committee citing health issues, said changes were made to a draft report on the Duffy audit, removing harsher language that was used in reports on two other senators' expenses, because Duffy had already paid the money back.
Wallin has already paid back at least $38,000 to the Senate, but told the CBC's Peter Mansbridge in an exclusive interview June 13 that she may have have to pay back more.
Auditors examined about $321,000 worth of travel expenses claimed by Wallin going back to January 2009, when she was first appointed as a senator for Saskatchewan.
Wallin has been invited to attend the Senate committee meetings next week.