Um, it passed a test upon arrival with no extra prep work so why do you say he didn't test it?
3ATM is the standard test pressure for a Bergeon style tester. If they pass at 3atm they will generally be OK to much deeper. That is the bog normal test setting, testing higher regularly rips the guts out of the tester.
He said he tested it to 3atm, not that it only passed to 3atm. While I do not advocate paying a dealer for a water test your statement above is grossly unfair and bordering on slanderous.
No amused.