When there are two opposing expert opinions in a medical malpractice case, is it appropriate for a motions judge to weigh evidence and make findings of credibility?

I am mindful of the latitude given to a motions judge to weigh evidence and make findings of credibility when it is just to the parties to do so (see: Hryniak v. Mauldin, [2014] S.C.C. No. 7, para. 66). However, when there are warring expert opinions as is evident in this case, I am of the view that justice is best served by a trial in which their evidence may be heard, tested by counsel and clarified as necessary through questions from the trial judge.