I wouldn't worry so much about warping as I would about chemical changes at that temperature. Colors are more likely to change and dyes are more likely to migrate as the temperature gets higher. It's a long term consideration; you probably wouldn't see any differences for several years (if ever) but storage in the 60-70 degrees F range would be preferable.

I'm not one to concern myself with PVC and the plasticizers that keep it soft, but higher temperatures are more likely to move the plasticizers from the plastic holders and pages to your chips. It's more a problem for tokens and coins than for chips, in my opinion.

Has the safe been in your house long enough to have cooled off from it's move? Remember, these big iron monsters have a large thermal mass and it could take days for the inside to accomodate itself to its new environment. Thats a plus for fire protection, of course.