The layout of the lab? That seems like something that could be public
Labs have sensitive areas too. Knowing the layout of them helps not just in-and-out operations but can also guide other kinds of educated guesses. Do lab staff in their offices have direct views of the lab equipment or are they separate? etc
The real issue at hand is that he is suspected of something worse than merely copying a lab layout. Is a laboratory setup even protected? In many cases an experiment will elude replication because the lab setup was not properly documented.