I have to say I think your programming skills are probably better than mine !
The views bit hooks to bbp_has_topics, so the args are the key part to get this going, rather than needing to alter php files
see
https://bbpress.org/forums/topic/adding-custom-view-shortcode/
for how another user got a custom view with meta data working – I’m a bit tied up at the moment to write the answer, but judging by your post above you should be able to work it out !
If you don’t then come back and I’ll try and help when I get some time
If you do, please post the whole solution here in the spirit of sharing – it would be a good one to have for other people, and to add as a plugin to the other plugin.