Exam PMI-RMP topic 1 question 123 discussion

During a major project review, the project manager discovers that large groups of internal management issues are obstructing progress. In reviewing the risk management plan, the project risk categories largely contain technical and customer relationship type risks. The project manager wants the risk management plan revised to account for these risk areas, particularly because the project has several more months before completion.
Who should the project manager collaborate with to revise the risk management plan at this stage of the project?