Currently, the power to compel someone to testify is that of a standard commission of inquiry. Consider the Charbonneau commission or other commissions across the country. A person cannot refuse to testify at such an inquiry. Therefore, in theory, the review board could compel the accused, who has become an applicant because they've been convicted and claim they were wrongly convicted, to testify before it to discover more.
I'm not saying that this is a good thing or a bad thing. I'm just pointing out the possibility. Would you be comfortable with the idea of such a possibility arising?
In a regular criminal trial, the accused cannot be compelled to testify. They have the right to remain silent. However, under such a process, the right to remain silent would, at the very least, be called into question. I'm not telling you that it would be declared constitutional if challenged, but there is at least some concern over it.