Many SilvaGunner works are available on the collective bandcamp, with individual artists listed. You can usually check on the wiki or so too if you need help figuring out what album to find something on.
For example if you want to find
https://www.youtube.com/watch?v=VhFO7DUKs0kyou would look it up on the wiki, finding
https://siivagunner.fandom.com/wiki/Haunted_House_-_New_Super_Mario_Bros.
it'll tell you what bandcamp album it's on, so you just double check with bandcamp to make sure the ripper and song title are correct
https://gilvasunner.bandcamp.com/album/7-grand-maverickso in this case it'd be 56.
artist: RHMan
title: Haun Point
tags: Haunted House - New Super Mario Bros.
Now the wiki shouldn't be your main source for info, it's just useful for finding out what albums the songs are on and who their creators are to look proper sources up.
If you still can't find any info, you may want to ask veteran SilvaGunner experts for help instead, like Stefan or something.
If
all that fails, then yeah, you'd fall back to the SilvaGunner - youtubetracktitle for your meta since it's the only recognizable info the song exists with in such cases.