[mothered]

they say it left their warehouse and because box doesn't look tempered with

Tell them to provide photographic evidence of the package condition at the time It was delivered to your address.

The photos must be clearly visible, and contain every angle of the package. I can assure you they cannot fulfil such a request.

I'll try

No matter what they say to dispute the claim, remain adamant with this:

provide photographic evidence of the package condition at the time It was delivered to your address.