Warning!!! We do not recommend this, but if you are persistent try it on your own cost.
For mirror booth, this is possible by carefully drilling the top of the booth with a size of 3/8” and use a knot to secure, knot size is "3/8- 16x3 hex tap bolt with a 3/18-16 wing nut" (please check photos below).
For other booths, most of our booths have a hole already on the top. To add a flash all that needs to be done is to secure the flash with the same knot.