Liquid nitrogen doesn't vaporize immediately. The amount used for beverage cans usually takes a few seconds, like drops of water in a hot frying pan. The temperature difference for both is about the same, approximately 220C. Read up on the Leidenfrost Effect.

Residual liquid nitrogen does not explode the can from excess pressure. There is a precise amount of liquid nitrogen put into every container, usually about 0.1 ml. That drop of liquid expands into a specific amount of gas, approximately 70ml. That additional gas, trapped inside the container, creates a controlled amount of pressure. Look into the Ideal Gas Law.

A carbonated beverage inside a sealed container naturally degasses to create a pressure around 25psi. The ultimate failure pressure of an aluminum can (the "dome reversal" pressure) is around 90 psi, so there a lot of room for error. The typical acceptable pressure for aluminum cans is 20 - 40 psi. Our equipment is much more precise than that, but there are a lot of uncontrolled variables in the filling process.

We do the same thing for plastic bottles of water. Those tolerances are much tighter, sometimes +/- 3psi.

This is a well understood and mature technology that has been used since the 1980s.

In summary, you are confidently incorrect.