Only if the applicant actually meets an Appendix 2 entry. The Engineer entry expects a degree or licence; a technologist with a diploma must independently satisfy the Scientific Technician/Technologist entry, including its direct-support requirement, rather than assuming the diploma establishes eligibility. The job title is not the deciding document; the transcript and the duties are.
Which entry does the transcript actually support?
Start by placing the diploma beside the two candidate entries. If the program is a mechanical engineering technology diploma, the Engineer entry is unavailable regardless of experience, because that entry does not offer an experience substitute. The Scientific Technician/Technologist entry can work, but it carries its own conditions: theoretical knowledge of the discipline, the ability to solve practical problems, and a role that supports a professional such as an engineer.
A distributor that wants the applicant to sign off on installations independently is describing a job outside the entry. The practical fix is for the employer to identify the licensed engineer who directs the work and to describe the technologist's tasks as support of that engineer's projects. If the employer cannot truthfully do that, the TN route is doubtful and a different category or a different role should be considered before any resignation.