Other mistake: When Brackett tells Johnny and Roy to contact the animal shelter via the disaster net, Roy asks the Animal Control guys for their disaster call, and it's given as 3-9-9-7-7-1-1, but in the closeup Roy presses channel 8 then punches in 4-2-1-6-5-3-7 on the scanner. Additionally, this model Regency Monitoradio / Executive Scanner Receiver has 8 channels, so it would have been impossible to press 9, as was stated by Dave.
Other mistake: After the officer hands Les the tranquilizer gun, Les asks which way the tiger went and the officer responds, "Down that aisle," and we see both men, who are standing right beside the self-serve ice cream freezer, moving slowly towards the aisle in front of that ice cream freezer. The problem is that in the next shot, we see the large tiger coming from that exact area in front of the ice cream freezer, as he walks toward the camera on the other end of the aisle. This means that the Bengal tiger, Les, and the officer would have all been standing in the very same spot, at the same time.
Answer: I believe you are speaking of the old man, Mr. Wilson. He's played by J. Pat O'Malley.
Bishop73
Correct, it was J. Pat O'Malley...he also played the grandfather with his grandson when their rocket exploded, and also played "Old Bill" in the episode with Ann Prentiss, where Gage saves the little girl from the burning tree house, and her mother falls in love with him.