if this were a prequel to Tim Burton's Batman...

[Slash Man]

Certainly nowhere in the script, the credits or the official novelisation is the second mugger identified as Chill. And the majority of fans online seem to regard him as Bob. Uslan's comments may be an attempt to retroactively address a common criticism, or perhaps the second mugger really was intended to be Chill. Either way, I'd be interested to hear what Sam Hamm has to say on the subject.

There was an old magazine interview where Uslan confirmed him as being Joe Chill. Might've been Starlog (I don't remember off the top of my head). What really seals the deal is that Uslan is the one who rallied for a second hood in the first place [with Joe Chill in mind]. He was opposed to having Jack Napier being the Waynes' killer, preferring the original mugger. The filmmakers met him halfway by adding a second mugger with the intention of him being Joe Chill to appease the comic purists.

Again, this isn't really mentioned because the name Joe Chill doesn't mean anything within the context of the movie; it only applies to comic book fans familiar with Batman's origin. The fact that it's not Bob's name mentioned in the script/novelization/credits should be more telling that it isn't the same character.

[OutRiddled]

I say its him.  He pretty acts and looks the same as the Joe Chill character from the comics.  The only thing he doesn't do is shoot the Waynes.

[Silver Nemesis]

In Tim Burton (Virgin Film) by Jim Smith a J Clive Matthews, the authors suggest Nick – the mugger in the opening scene – was visually modelled on Chill as he appeared in Batman: Year Two. From page 71:

The mugger who points a gun at the young family in the very first scene is visually patterned after Joseph Chill, the murderer of Bruce Wayne's parents in the Batman comics. This deliberately and subtly assists the suggestion that the assault we are witnessing is the robbery in which Wayne's parents died – which would be an obvious place to begin a Batman film. Chill can be seen in Batman Year Two written by Mike W Barr, originally published in Detective Comics #575-578 (June-September 1987).

Nick certainly looks closer to the comic book Chill than the second mugger in the flashback scene.

By contrast, the second mugger is dressed similar to Bob in the opening act of the movie.

I'm not saying Uslan's wrong here, or that the second mugger isn't Chill. I'm just noting some observations to support an alternate reading of the scene.

[OutRiddled]

If that's Bob the Goon..  well both the actors are about the same age if you check IMDB.  Clyde Gatell and Tracey Walter were born less than a year apart.  And this scene is supposed to take place 20-30 years ago.

[johnnygobbs]

If that's Bob the Goon..  well both the actors are about the same age if you check IMDB.  Clyde Gatell and Tracey Walter were born less than a year apart.  And this scene is supposed to take place 20-30 years ago.

I agree.  Plus they don't really look much alike.

By contrast, I do think that Hugo Blick looks like a younger and much thinner Jack Nicholson/Napier, in the flashback scene.  He has the perfect arched eyebrows and demonic grin.

[Silver Nemesis]

What if Bob and Chill... are one and the same?

[Silver Nemesis]

I'm not sure if this has been posted before, but here's a Batman Begins Keaton deepfake.