Re: J
Probably not. Since he had physical access to the machines, he was able to install the software, which then sends him the information. Firewalls only protect against incoming traffic, not outgoing. Further, if the machines were to initiate an outgoing connection to his machine, he would be able to "shovel a shell" across the connection, turning it in essence into an incoming connection.
When physical access is granted to a machine, all security is considered null and void, or so the saying goes...