My view is that yes, there is no need for the witness to be swearing on a Bible before he or she gives testimony. They are obliged to speak truthfully to a parliamentary committee.
However, if you walk over and seek remedies under the Criminal Code, then the rules of the Criminal Code may be brought to bear. As Mr. Tardi pointed out, the Criminal Code clearly requires that the person alleged to have been perjurious was giving a statement under a sworn oath.
Now whether the court would accept that there is a legal obligation to speak truthfully to a parliamentary committee and that this applies even in the absence of the swearing of an oath, I can't be sure. But the Criminal Code seems to require the swearing of an oath for any charge of perjury to be laid against someone regarding a false statement.