Relevant recent work, training and contributions can support that account. The evidence should concern the person, not only the company’s product release.
Identify the actual involvement
Explain whether the employee designed, tested, supported or merely observed the update. Keep each contribution accurate and tied to the planned duties.
Contemporaneous internal records: design and configuration documents, change histories, authored training material, project files, and any registered intellectual property, together with the standard relationship and payroll evidence. With the organization's own records: protocol authorship and revision history, validation and deviation reports, training materials, and a signed statement quantifying how many employees hold comparable knowledge and how long a replacement would take to train. Describe what the knowledge does and how it was acquired, and attach documents that prove existence and authorship — cover pages, version histories, training records — rather than the technical content itself. Documentation of the process is more persuasive: internal design notes, control parameters, revision histories, training material written for the company's own staff, and any confidentiality treatment applied to it. Evidence should include the library itself or representative extracts, revision history, the training curriculum, records of who has completed it, and a comparison explaining what a competent planner hired in the United States would not know. At first review, list each claimed element of knowledge beside the company record that proves it: a controlled manual, internal test result, restricted software setting or dated revision history.