I just managed to platinum Innerspace after encountering the 3/4 relic counter for Duskprism glitch.
I was able to fix it by returning to Duskprism from Sunchamber (the location to the green ring is inside the structure directly beneath the large yellow sun orb) and by flying through the big sliding doors down toward the bottom of the large cave-like room. I entered the second lowest tube which led me to a large room containing a window, some structures, and multiple other exit tubes. I left that room via a blue tube with sliding doors, and continued along it until I saw cracks in the wall of the tube, which I broke through. I was now in a a smaller room containing a flower tube, which took me to another room (the one visible through the previously mentioned window) containing a square structure with two blue triangles at opposite corners. I flew all the way to the bottom of the hole in the center of the structure, and once hitting the bottom of the hole, turned around and flew back out, which made two blue orbs appear above each of the two blue triangles. I flew into and escaped each blue orb, at which point the counter changed from 3/4 to 4/4, and I got both the Loremaster and the platinum trophies.
I hope this helps someone.