For anyone who booked their 2nd PCR at 'Kata Center' in Phuket, the information is very scarce. No address online or anything. The reception at my hotel told me I should take a cab as they all know where it is. I planned ahead and asked local Kata hotels and eventually found it. For anyone who's riding solo, it's actually located at the Malisa Villa Suites (5-star hotel).
TLDR : Answer Summary
The Kata Center for PCR testing in Phuket is located at the Malisa Villa Suites, which is a 5-star hotel. While there is limited information available online regarding the center's address, local taxi drivers and hotels in the Kata area are familiar with its location.