Again I'm not accusing you. I just think that's amazing.
As for my method with Sonic that I set many years ago, you're wrong. He can escape. A user here named eredani showed me how.
At the very beginning of the stage, I initiate Wheel Glitch to enter Knuckles' sector, as opposed to the bat lure method.
(To activate this glitch, you need to walk into a series of balloons, touch the bottom of the wheel with three ring boxes underneath it, then land on those boxes. As a result, you'll end up with your character following gravity rules which most closely resemble Mad Space from SA2B. But be careful! Jumping disables the glitch.)
In my run, I cleared out everything in Knuckles' sector except for the area near the start which has a barrier and three rings behind it and the area near the second checkpoint, since you cannot jump back up from there.
(This, by the way, is why I am desperate to figure out your method. There's untapped potential here you're not seeing. I promise you I'm not accusing you, I just really need to know how to do what you're doing, because I know of like 50 places in other levels where this could be applied.)
As for returning to Sonic's home path, you have a launchpad of sorts, thanks to eredani. The main Knuckles route with all the candy-cane twists leads to an area with several bats. Up above that are a long series of anti-grav fans.
All you need to do is charge up a spindash early on in the path, convert your stance to running by doing a downhill jump where it's appropriate to do so without losing speed, then jump as the last curve before the fans starts to curve back to horizontal. With decent timing and angle of your jump (Doesn't have to be perfect), Sonic will pass to the right of the obstacle above him so he will continue going up without bumping into it. The fans will catch him and pull him up if you approach the fan perpendicularly.
A Lightning Shield will also help you accomplish this jump if you somehow fall short.
I then clear out all of Sonic's area, except for 25 rings: two boxes on a mutually exclusive path with the rest of Knuckles' sector, and a string of 5 rings just before the boss (which you are trying to show me how to collect).
I then return to Knuckles' sector using a double bat lure. After getting the bat from the path way to the left (an output point for a yellow spiral launcher), I lead him down a path near the next yellow spiral tube, with fans beneath it. I let it hit me, losing my shield. I then grab the lightning shield in the alcove to the left, and lead the bat to another set of fans -- this one leading to the remainder of Knuckles' sector.
I finish the stage in the Knuckles path.