A project has been experiencing some difficulties due to third-party vendors. The project manager should request.

Requesting additional resources addresses capacity or staffing shortfalls, not the documentation and management of risks introduced by external vendor problems.

A gate review is a formal phase-end checkpoint used to authorize moving to the next project phase, not a mechanism for managing ongoing vendor-related risks mid-project.

The risk register is the appropriate project artifact for recording, analyzing, and tracking identified risks - including those stemming from third-party vendors. Updating it ensures the vendor issue is formally documented with probability, impact, and a risk response strategy, enabling the team to actively manage and monitor it going forward.

A performance audit evaluates whether a vendor or process is meeting defined standards, but it does not serve as the primary tool for identifying, documenting, and tracking risks in the risk management process.