Do you have a link to this holder so we can see it? There seems to be more than one choice.
Are you talking about this?
Color Keeper Stand & Store | Totally Tiffany products
I find this hard to judge in pictures myself. Do you want it only for Tombows?
Given that Tombows are narrower than Copics and Spectrum, anywhere they fit the Tombow will too. It is also possible that they will fit that back row where there are pencils...if that is elastic straps holding them. But I dont know about height. I think they are longer than a pencil so it depends on how much elbow room there is.
Are you looking for a portable carrier for them?
These might be choices:
https://www.amazon.com/Tombow-Storag.../dp/B00GID96RQ
I think Blick gives this for free if you buy the 96 set.
This one is smaller, but from the UK...if you can get the dims...and check colored pencil cases you might find one here that works. Or order it-that price is pretty good-the pound is about 1.30 now, so that's going to be under 10 bucks. I cant seem to find it domestically.
Crafts too Pen Storage Case for Sakura, Tombow and Distress Marker Pens, sirstampalot.co.uk