The content that you used is... strange (even in view mode); does it come from some real-life usage, and you just removed some parts of it, or how did you end up with such content? The PDF export can't work well with any "random" HTML/CSS/JavaScript. We want to make sure it works with the content / wiki syntax / styles that are commonly used by our users, i.e. that makes sense in real-life (otherwise we risk spending time fixing bugs that none encounters / cares for)
When reporting a JIRA issue is nice to also think about the other users that may encounter PDF export problems and are looking for reported issues. The question you should ask is: is my problem generic, i.e. could it affect other users as well or is it specific to my setup / environment / content? In the case of this issue you say that "Not all images are showing in the PDF export" without mentioning how are those images displayed: in a very large table with colspan and rowspan. If you replace those images with some plain text you'll see that the problem has nothing to do with images. The PDF export has problems exporting tables with colspan and rowspan independent of their content.
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