Auto-translated
First attempt, and it didn't quite work out. I tried to replicate exactly how Zakhar did it... and it failed xD
Okay, let's go through it step by step. As far as I understand, almost everything is the same, except for the most important thing: they don't upgrade in my castle xD
So, the interface has picked up the changes and displays them correctly, and it functions correctly (it deducted the resources for the construction).

They don't appear in the hiring window (although I didn't really expect them to, since there's no slot), but it's as if they exist.

When you click on "upgrade," the Archangel simply reverts to its previous form without any options.

But if you go to the Fort on the Hill, it offers me the option to upgrade the Archangel.

In the creatures, I also added the upgrades, just like Zakhar (I was making Higher Archangels from Death Knights, so don't be surprised by what's written xD).

From all this, I concluded that the problem is specifically here, but what it is, I personally don't understand =(

But just in case, I'll post screenshots of other files, in case I'm wrong and the problem is there:

UPDATE: By the way, the Altar of Erathia also appeared in the map editor.