The TN letter should not even mention your qualifications, as that is for the you to prove to the border guard.
The TN letter should only describe the job and how the job qualifies for a TN. The fact that you are being offered the job shows that the comapny is satisfied with your qualifications for the job.. Whether you are qualified for the TN is to be determined at the border.
But, in this case, how does "over 4 years" and 62 months disagree?