Ghouls in 2nd ed are typically "savage" or feral as the game presents them as mostly having become feral due to the shock of Goblinization and how it affected their mental stability (the Krieger Strain of the HMHVV is introduced in a later source-book -- I can't recall which one at the moment, apologies). However, yes, with a racial max of 4, it's very conceivable that an individual or a group of ghouls could be able to function in normal society (too bad they're shunned and hunted down, sort of makes it more difficult for them). Or, at least, be functional enough to be crafty (I believe that was the initial goal with Ghouls). In the "Eyewitness" game module, we encounter a ghoul with an Int rating of 6 who is not only able to function properly but strive on a corporate level.
In the end, ghouls are what you want to make them.
So far as tracking goes, your player's idea is not a bad one. It would be appropriate, I think, to give the ghouls a +2 to +4 modifier on their Perception Test TN to spot or track him by scent (depending on how thorough his scent-masking is, and how convincing you find it to be). Keep in mind that real-world animals, such as the bloodhound and bear, are rarely fooled by scent masking. The reason is that everything leaves scent markers behind: skin cells, hair, chemicals, etc. So you could rule that in your campaign, a ghoul's sense of smell is acute enough to compensate for their bad eyesight (and makes them on par with a bloodhound or bear). One way you could go about it is adding the ghouls' Essence to their Perception dice to reflect the Enhanced Senses Power and resolve scent-based Perception Tests.
However, as others mentioned earlier in the thread, ghouls are Dual Nature beings (Essence 5), and would likely be capable of tracking him astrally (this time using their Essence score for an Assensing Test (if you plan on using it for a tracking test)).
Remember that whichever method you decide upon is ultimately your call -- and, so long as it makes sense within the bounds of the Rules as written, your player should accept your judgement call on it.
Good luck and have fun with your ghoulisheries!