I contend that since the liner notes list “featuring XXX” on only five tracks, it’s clearly intended that those artists are given a “featuring” credit on the track.
Another user contends that since the featured artist does not appear on the song list on the back cover, they should not be listed as featured artists.
I’ve personally added credits like these for my CD copy of 4×4=12 by deadmau5*, but I don’t know that there’s guidelines for this exact case yet. I think it does make sense to add artists featured like this to the artist credit, whether physical or digital (I feel like I’ve seen credits like this on Bandcamp and/or YouTube too)
*scans aren’t present, but the featured credits are in the booklet in a similar form
edit: went ahead and made the thread title more descriptive