If you can put it in the camper, do that instead. If you can mount it to the camper, do that, but also be aware that this bike has a reputation for making trailers tongue light if you mount it behind the camper instead of between the camper and the vehicle.
If this photo gleaned from the interwebs is accurate, the bike will just barely fit if you angle it across the diagonal. The bike's overall length is 78" and calculations of the cargo space say the longest diagonal dimension is sqrt(66^2 + 44^2) =79". The error margin is too low for me to try something like that myself though and that sounds unsafe with hard braking.
- Assuming you could teleport it in, the front wheel off option would work better. The cluster on the front is taller than 32". The seat and rack are both below 32" though.
- This bike has 17" wheels, so in theory you could probably reclaim up to 17" or so by removing both wheels (give or take for fenders). You will still need to relocate 200'ish lbs of bike inside your vehicle if you do that. But it would probably fit with both wheels off.
- It's worth noting that if you were thinking of using a dolly under the stock crash bars, those aren't designed to hold the weight of the bike, let alone the weight of the bike + tie down straps.
On the global forum for Tern GSDs, I couldn't find any photos of a 4Runner with a Tern GSD cargo bicycle inside it and wheels on (length: 72") which is smaller, shorter, and lighter than the CT125. Note that the Tern GSD is specifically designed to be wheeled into the back of a car exactly as you describe.