Probably not but I would elevate the lamp anyway.
I have this screen on an enclosure but have 1x2 mdf supports that the basking lamp rests on.
The other problem would be your cham hanging on the top of the enclosure and getting (IMO) too close to the lamp.
edit: yes, that would be bad.....but my name is Brad
And now I will agree with Brad. I would never have a basking bulb sit directly on the the screen regardless of the material used. Given time at some point the cham is going to crawl on the screen right under the lamp and potentially get burned. There are many creative ways to elevate the lamp.