
Visible crew/equipment: When Picard, Data and Worf are on the planet, just a few shots after they leave the shuttle, Picard drives a sharp left curve. If you look at him in this shot, it is not Patrick Stewart sitting on the driver's seat, but his stuntman, who is not even wearing goggles. (00:12:45)
Answer: Long range sensors can show the general location of specific ships (this is part of the reason Romulans and Klingons use cloaking devices). All Shinzon has to do is find a remote planet close enough to the Enterprise that would cause them to be the most prudent choice to investigate. It's definitely a gamble but not one that is made without calculation.
BaconIsMyBFF