What kind of analysis was done?  If it was Static Structural, then the contacts are sufficient to compute a solution. I never use the word perfect to describe any model. All models are wrong but some are useful.

A modal solution will complete without errors even if the contacts are missing. The clue that the model is useless is if the first six natural frequencies are practically zero. This indicates a mistake in the contacts. You can find out which body is missing a contact by plotting the deformation. One body will have very large deformation relative to the body that is supported.

You don't look at stress and strain in a Modal analysis. Do that in a Static Structural model.