The parser assumes that this is HTML and in the default setup HTML is stripped from your markup. Add the following parameters to your config.toml and they should turn up:
goldmark:
renderer:
unsafe: true
If the code now is in the output, but invisible then your problem is, that the browser interprets it as a tag, but can’t identify what tag it is. In that case replace < with < and > with >. If you have access to the layout files and can add some code then have a look at htmlEscape:
The lines that get through do so, because they contain invalid markup (the dot and the question mark) so the parser sees them as normal text.