1. ANY glued panel can delaminate. Wood backing or Styrofoam.
2. Usual cause is water intrusion and sometimes lack of adhesive(missed area) at build.
3. Wood backed Lamination can use most adhesives
4. Styrofoam backed MUST use a water based adhesive. If NOT, then the wrong adhesive will "melt" the styrofoam., Then you have a much bigger problem. MORE problems happen with Styrofoam than wood backing.
5. Lamination and warranties, they usually state, that IF ANYTHING is added or modified to the exterior walls(cuts holes or added screws) will VOID the warranty. Reason is, these are possible egress points for water intrusion. This is why, when you or the dealer want to add or modify the exterior walls of a RV under warranty, you need to get the OEM to sign off and allow this type modification and will then warranty for the warranty term.
6. Most common problem I have seen is when a dealer or customer wants the Over the Range Microwave/Convection Oven vented to the outside and the OEM vented to the inside. Because the hole cut and sealing of the outside vent was not done correctly the wall delaminated from the water intrusion. WHICH the OEM denied warranty.
7. SO, wood backed or Styrofoam, BOTH are good and most problems happen because of water intrusion. Doug