The silver suit couldn't insulate and keep the heat out?
If you so wish to believe...
The problem is that there is no air to carry away the heat so that whole setup becomes like a miniature greenhouse. Without some active way to cool it eventually you'd cook.
From the videos I’ve seen, it’s also spinning really slowly. I think you could see off-gassing in some of the videos. I looked into it a little further, and there was speculation it was from the plastics and paint getting extremely hot in direct sunlight.
“Space” is roughly the same temperature (a little warmer near stars with particles and free gas), but the direct solar radiation is what is so hot. Since space is an excellent insulator, getting rid of the thermal energy becomes a problem when you’re not shaded.
If you want to read some more on this, check out what the JWST has done for thermal management. It’s really cool (no pun intended).