I am not knowledgeable of the Canadian judicial system(s) and I can only speak based on my litigation experience in the US.
It seems very unlikely to me that court filings for the type of claim(s) you are pursuing are confidential or sealed. Thus, other than an actual knowledge of Canadian laws indicating the contrary, presenting them the document(s) is fine from the standpoint of procedural law.
Regardless of Canadian laws in that respect, showing to potential witnesses --especially in the case of adverse ones-- the court documents prematurely might be detrimental from a tactical/strategic standpoint. Keep in mind that your records and any statements you make when speaking to them might give them and the defendant the opportunity to fine tune a perjured testimony for when they are called to testify. Many witnesses lie even when they are under oath.
Instead, you should focus on how you will examine their testimony when they are called to testify. For instance, think of the follow-up questions you should make, be it to support your claims or to lead them to inconsistencies in the event that they indulge in perjured testimony.
It is possible that the defendant will make very narrow questions to his witnesses so as to merely "corroborate" his allegations. By contrast, your job will be to make them elaborate on --or testify beyond-- defendant's very narrow questions to the extent that their testimony (or answers thereto) is (are) relevant to your matter.