The design library, modelling files and commissioning procedures the employee produced, with dates and authorship; internal training records; project histories showing systems he brought online; the American position description; customer contracts describing installed systems; and payroll evidencing the continuous qualifying year.
Let the artefacts carry the argument
Gather the material before anyone writes persuasive prose, then let the petition describe what the documents show. Print file headers with creation dates, pull the service records for the installations he commissioned, and collect the training material he prepared for the subsidiary's staff. Include the American position description prepared independently of the petition, since a job description written for the business reads differently from one written for an application. If the company keeps very little in writing, which is normal in a small manufacturer, begin documenting now and describe the position as it genuinely is; a modest record explained plainly is defensible, while a reconstructed one is not. Ask the subsidiary to add whatever it holds on its own side, such as the projects already sold and the customers who specified these systems by name.
Hypothetical example: a Tyendinaga pharmaceutical-packaging supplier relies on an internal manufacturing protocol to explain a transfer. The file should identify the protocol without exposing unnecessary confidential detail, then show authorship, restricted access, training records, and why the U.S. role needs that knowledge. Pair those records with payroll and employment evidence for the foreign year. A declaration that something is confidential, without supporting controls, does little on its own.