You make some good points. Until the Dunlop and VMS appear at trial nothing must be proven by either side. At trial, Dunlop must prove (on the balance of probability) that the facts are as he alleges in the statement of claim. VMS will argue that the agreement is fully set out in the written agreements and that there are no collateral verbal agreements, that alter the written agreements. In the absence of convincing evidence and/or arguments to support Dunlop's position, VMS position will be sustained and Dunlop's claim should be dismissed.
That is why VMS will take as much time as it takes to fully review Dunlops case / evidence that he will disclose during Examinations for discovery and than push for a trial.