Is it possible to user flutter_markdown custom builder with expandable widget?

Question

I want to represent markdown string as expandable widgets with title and collapse content. I use the expandable plugin to create widgets with collapsed content and the flutter_markdown plugin to render content under the title in collapsed area. But I need to parse the markdown myself into my own model classes.

I found out that the MarkdownBody widget has an builders field, in which we can specify our own widget that should be used for render specific markdown tag. As I understand it, it is intended for custom rendering of any tags (classic, your own tags or tags from extensions).

Can I use a custom MarkdownElementBuilder to create multiple tags display in one widget (h2 and following p im my case)? How can I achieve the result as shown in the screenshot using the custom MarkdownElementBuilder?