As a Principal Infra Developer, you are expected to design and develop infrastructure solutions for clients. The job role would also require you to connect with respective teams to understand client demands. As far as the role of a Lead Administrator is concerned, you have to supervise volunteers and manage and monitor the operations of hardware and software systems in the company.
8+ years of experience is a lot. With that level of experience, the designations offered to you by Cognizant and Wipro seem valid. But when you compare Cognizant vs Wipro, it is better to consider the designation of Principal Infra Developer at Cognizant than Lead Administrator at Wipro. The former is in a higher position than the latter one.