How often is the village census taken?

Solution 1:

I believe your information about the "census" is as outdated as the rest. In 1.14+ there's no population cap as such. Simply, the two villagers breeding AND their baby must be able to pathfind to their beds (not necessarily reach them; pathfinding has its quirks like misinterpreting trapdoors). The check occurs at the moment of attempted breeding; breeding won't be attempted if one (or both) of parents doesn't have a pathfindable bed. It will fail (cloud particles) if there's no free bed pathfindable by the child.

The distance of the child from the parents doesn't matter - the position may be quite close but must be unable to pathfind to its bed. You should also take into account bugs - occasionally villagers fail to free up beds they are no longer able to pathfind to. You'll need to break and replace such beds in this case.