Shema for buddyboss Replies (Comments)

Trying to create a custom Schema template for the newly released DiscussionForumPosting https://developers.google.com/search/docs/appearance/structured-data/discussion-forum?hl=en#dfp

However, i am stuck at the “text” variable, as there is no way to link it to the specific comments content using rankmath. I can’t use %excerpt% as this would refer to the main discussion topic’s excerpt and not the comment’s

},
? ? ? “comment”: [{
? ? ? ? “@type”: “Comment”,
? ? ? ? “text”: “%excerpt%”,

Buddyboss does create a sepearte ppst for each comment (reply) so how can i tell rankmath to source its excerpt?