According to the GDPR, personal data shall be collected for specified, explicit and legitimate purposes and not further processed in a manner that is incompatible with those purposes1. This means that a business unit can only use personal information for a different purpose if it has obtained the consent of the data subject, or if it has a clear legal basis or obligation to do so2. Therefore, informed consent should be the first consideration when a business unit wants to use personal information for a purpose other than for which it was originally collected.
References = GDPR Article 5 (1) (b) and Article 6 (4)1, ICO Principle (b): Purpose limitation2

First-hand direct observation of the controls in operation is the best way to confirm the existence and operating effectiveness of information systems controls because it provides the auditor with the most reliable and persuasive evidence. Direct observation involves inspecting the physical and logical aspects of the controls, such as the hardware, software, network, data, procedures, and personnel involved in the information systems. Direct observation also allows the auditor to verify that the controls are functioning as intended, and to identify any deviations or weaknesses that may affect the reliability of the information systems. Direct observation can be performed by using various techniques, such as walkthroughs, inquiries, inspections, reperformance, and analytical procedures1. References = Auditing Standard No. 13, The Auditor's Responses to the Risks of Material Misstatement, PCAOB, 20101

A heat map is a graphical tool that displays the level of risk severity for various risk scenarios or categories using different colors, shapes, or sizes. A heat map is most helpful in providing a high-level overview of current IT risk severity, as it can show the relative importance and urgency of the risks, and highlight the areas that require attention or action. A heat map can also help to communicate the risk information to the stakeholders, and facilitate the risk prioritization and decision making. References = 5

The best recommendation to address the situation where personal information from the production environment is required for testing purposes in non-production environments is to de-identify data before being transferred to the test environment. De-identification is the process of removing or modifying any personally identifiable information (PII) or other sensitive data from the data sets, such as names, addresses, phone numbers, email addresses, etc., so that the data cannot be traced back to specific individuals. De- identification protects the privacy and confidentiality of the data, while still allowing for testing, analysis, or training purposes. Enabling data encryption, preventing the use of production data, and enforcing multi-factor authentication are also useful measures, but they do not eliminate the risk of data breaches or unauthorized access to PII. References = Risk and Information Systems Control Study Manual, Chapter 3, Section 3.3.1, page 3-21.

According to the CRISC Review Manual1, cost of controls is the amount of money or resources that an organization is willing to spend to implement and maintain risk responses. Cost of controls is one of the factors that influences the risk appetite of an organization, as it reflects the trade-off between the benefits and costs of risk responses. Cost of controls helps to determine the optimal level of risk that an organization can accept in pursuit of its objectives, and to align the risk responses with the organization's strategy, goals, and culture. References = CRISC Review Manual1, page 193.