Does Thule Yepp Mini (behind handlebar seat) fit?

[MrGroob]

Hi everyone! I'm thinking about getting a Radwagon 4.  One question I have right now, is whether this bike will work with the Thule Yepp Mini seat that I have for my son? Be loves sitting between me and the handlebars and being up where he can see everything, but looking at the space between the rider seat and the handlebars I'm worried it'll be too close.  I haven't been able to look at one of these in person yet, and kiss really hard to tell looking at pictures

Has anyone tried this child seat on the Radwagon 4? Does it work? Or too tight?