Perhaps he had other reasons. Most accounts from the time said that the judge allowed the demonstration. But immediately after the demo, when the NTP lawyers asserted the demo was fraudulent, the judge left the room, returned, chewed out the RIM lawyers and then summarily ruled against RIM, saying the infringed on multiple patents, then dismissed the demo and sent the jury to determine a verdict.
Doesn't sound like he had or needed additional reasons.
Your account is wrong. First, the judge does not rule on infringement unless it is summary judgment. And in summary judgment there is no jury verdict. You have both the judge and jury determining verdicts.