ircd: messages not always traversing hubs to leave nodes

Imagine this simplified layout

eotl
 services
 vert
    veleno
    digdist
  cvs
    magnumuk
    sestar

I quit all the channels that I was on and left IRC and rejoined.

[19:25] * Now talking in #aaa
[19:25] * nelgin changes topic to 'Do not join this channel or you will be akilled automatically'
[19:25] * Now talking in #zzz
[19:25] * cvs.synchro.net sets mode: -o nelgin
[19:25] * nelgin changes topic to 'Do not join this channel or you will be akilled automatically'

Now, if I go to vert, veleno and digdist and /LIST I see that the topic is set on both channels.

*** #aaa       1      Do not join this channel or you will be akilled automatically
*** #zzz       1      Do not join this channel or you will be akilled automatically

If I connect to cvs.synchro.net I can see #aaa but not #zzz.

If I who /WHO #zzz then I get
#zzz       souriest  H   ~praewm@101.red-88-15-25.dynamicip.rima-tde.net (bluabled)
#zzz       nelgin    H*  nelgin@47.186.47.220 (...)

Definitely not on the channel.

If I do /WHO #aaa then nothing is returned.

Now if I go to a leaf connected to cvs, let's go with magnumuk and /LIST

*** #aaa       1      Do not join this channel or you will be akilled automatically
*** #zzz       1

Once channel is set with a topic and one isn't.

#zzz is the channel from which I was deopped when first joining, however the channel modes are not set to +t.

I could go down a rabbit hole of testing what works and what doesn't but I think it's clear, something, somewhere it not behaving correctly, probably starting at cvs for deopping the first user on an empty channel.