Do you think he had TCAS RA? I had mode C and TIS installed in a Garmin 430 and had TA on him, but TIS (traffic information system) is not a full TCAS.
No - you only get a RA when the other guy also has TCAS. He may have received a TA "Traffic - Traffic".
Was he right in your opinion?
No he wasn't - you don't always see the traffic that generates your RA.
PM