What can go wrong? Inside is probably a cadmium sulfide photoresistor. If it's like these, the conductive path follows a serpentine pattern, which kinda looks like an inductor. The inductance is probably fairly small (I couldn't find a number). At
1MHz, the inductance probably has little effect, especially with the padding. However, if things act strangely in your testing, you might want to measure the inductance with a common LRC meter.