Some mentioned the lack of interest in the B&W world for "neutral" as a worthy goal, and this would carry over into the 3rd party inks as well, few of them set that as their design priority, or achieve that. "Pleasing" has always been a subjective goal in B&W, both darkroom and ink. So the Canon B&W output may not have been designed specifically for that either, though I don't recall seeing really problematic casts.
The only approach attempting to hit neutral, actually, is color managed color printing. Unfortunately, ink use is not very for B&W output, and the higher colorant component risks more metamerism failure, and now we're back to the viewing and lighting issues others have mentioned. Additionally, color profiling has a lot of tradeoffs to balance when building a profile, obviously perfectly neutral B&W is not necessarily high on the list as opposed to other color matching issues. Extended target profiling like Data Color and spot optimization in i1Profiler may address those issues.
So for niche B&W options, 3rd party drivers have been great for B&W ink, but again, hitting dead neutral is generally not the goal, placing control of your print hue in your hands, with more options intended for B&W enthusiasts, is. So, given the user controls, you may find "neutral" with some tweaking, or many other print hues you will be happy with.
As stated, QTR does not support Canon, but True B&W does, and it's a great tool, definitley worth trying in demo. But again, I doubt you will find a "default" neutral option. All the tools for you to learn and pursue that will be there though. There will be work to do.
I think your options are to thoroughly master the B&W abilities in Canon's plugin, attempt extended gray color profiling using the color driver, and demoing True B&W. If none of that pans out, look at an Epson/ 3rd party ink option. But again, as hitting dead neutral is not a priority with any of these options, except perhaps color profiling, you're on your own to find it, once tools are in your hands to achieve it.
My apologies if all this has been covered in other posts, visible or invisible.
Tyler