What product did you use exactly? Not just the brand, the product itself.
Also, what kind of wood did you use?
But in general the biggest issue with cage sealants is when they are exposed to moist and/or acidic substate all the time. Moist cypress mulch, for example. Cage walls are not as big of an issue. Water droplets evaporate and/or roll down to the cage floor pretty quickly.
As such, the cage floor and first few inches of cage wall are the areas that need the most protection. Cage floors should really have some kind of plastic lining. The first few inches of cage walls should also be lined if a moist/deep natural substrate will be used.
But pegboard is difficult to seal properly and allow direct moisture contact. I would avoid spraying these areas.
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Current snakes:
1.1 Gonyosoma oxycephala - (Silver/Yellow)
2.2 Gonyosoma oxycephala - (Green)
4.3 Gonyosoma janseni - (Black)