If I understand your question, you only need Perl to decode file you already have?

And as far as I can tell from some quick scanning of the docco, zsero "files" include some (compiled?) metadata about the structure,
and a bit stream of the actual data.

After having a quick look over the wire format at https://zserio.org/doc/ZserioEncodingGuide.html

It looks like most of the actual work can be done by pack/unpack and a few %hash lookups.

If there is need I could probably whip up a PP reader
🤷‍♂️