I drew a very scientific diagram for you - this is a cross-section with the back of the tank on the left. The plug sticks out of the back of the heat panel with a very small clearance above and to the side, the blue circle in the pic. The cord is tightly secured against the ceiling and she's unable to move that part of it but rests her weight on the plug, and if I interrupt her she squeezes herself sideways out of the gap. I don't like her jamming herself into such a small space or spending time that close to the heat source.
Here is a very scientific diagram of what it looks like from the front of the tank when she's stuck in there
She's been in the enclosure for around 2 and a half months and seems to mess with the heater/thermostat probe more when she's bored or hungry, so I've been making sure to get her out for exercise. She's being fed today so I don't expect issues while she digests at least. I'm hoping I can superglue a rubber stopper or something to the ceiling above the plug to make that gap inaccessible but I was curious if other people had had to plug similar spots, and what I need to be careful of to not disrupt the heat panel function.