Formal certificates are not the only evidence of specialised knowledge. The employer may use other credible records and detailed firsthand explanations, but still bears the burden of establishing the employee’s knowledge and the other requirements.
Assess what the gap really means
Determine whether the employee learned through experience, whether documents were lost or whether the claimed knowledge is not yet established. Use actual assignments and a supported learning history where available. Missing certificates do not create an exemption from proof, and a newly written letter should not invent a training programme that never existed.
Ownership of this question is often misplaced. The employee knows what they learned; the trainer knows what was taught and how unusually; the employer knows how the knowledge is used in the business and whether colleagues hold it. Counsel weighs those accounts against the standard.
A declaration written by someone holding none of that knowledge adds length without adding proof. Hypothetical example: A farm-management software firm supports a developer’s transfer with a letter from a regional director who never worked on the product, while the architect who designed its herd-records module, and who can explain why the approach is not generally held in the field, is asked for nothing. Identify the person who observed the work first, then decide which documents that person can point to, rather than drafting the letter and hunting for a signatory afterwards.