The stakeholder engagement plan and communication strategy are two key documents that guide the project manager in managing stakeholder expectations and interactions. The project manager should review these documents to identify the level of interest and influence of the stakeholder from the legal department, and determine the best way to communicate and involve them in the project. Escalating the issue to the project sponsor may not be necessary or appropriate at this stage, as the stakeholder may not be critical for the project success. Engaging the stakeholder and ensuring all requirements are captured may not be feasible or effective, as the stakeholder may not have any input or interest in the product design. Reviewing the product requirements and updating the stakeholder register may not address the root cause of the stakeholder's lack of participation, as these documents do not specify how to engage and communicate with the stakeholder. References:
* A Guide to the Project Management Body of Knowledge (PMBOKGuide) - Seventh Edition, Chapter
13: Stakeholder Engagement, Section 13.2: Plan Stakeholder Engagement, Section 13.3: Manage Stakeholder Engagement, Section 13.4: Monitor Stakeholder Engagement
* Professional in Business Analysis (PMI-PBA) Handbook, Section 2.3: Domains and Tasks, Domain 2:
Planning, Task 5: Plan Stakeholder Engagement
* Professional in Business Analysis (PMI-PBA) Examination Content Outline, Domain 2: Planning, Task 5: Plan Stakeholder Engagement