The most important factor to ensure that electronic evidence collected during a forensic investigation will be admissible in future legal proceedings is to document evidence handling by personnel throughout the forensic investigation. Documentation is essential to establish the chain of custody, prove the integrity and authenticity of the evidence, and demonstrate compliance with legal and ethical standards. Documentation should include information such as the date, time, location, source, destination, method, purpose, result, and authorization of each action performed on the evidence. Documentation should also include any observations, findings, assumptions, limitations, or exceptions encountered during the investigation. References:
* CISA Review Manual (Digital Version)
* CISA Questions, Answers & Explanations Database

The most important consideration when assessing the adequacy of management's remediation action plan is the criticality of the audit findings, as this reflects the level of risk and impact that the findings pose to the organization's objectives, performance, and value. The IS auditor should evaluate whether the remediation action plan addresses the root causes, mitigates the risks, and resolves the issues of the audit findings in a timely and effective manner. The IS auditor should also consider the feasibility, reasonableness, and measurability of the remediation actions.
References
ISACA CISA Review Manual, 27th Edition, page 256
How to Write an Audit Finding - Dallas Chapter of the IIA
How to Write an Audit Report: 14 Steps (with Pictures) - wikiHow