I’m contacting Dali today to price out driver and crossover replacements so I have some ammo when the insurance adjuster comes
The seller is the insured party so it’s up to him to file a claim and deal with the insurance. The insurance company will not deal with you because you did not buy the insurance. You are not the insured party. Once you accept the delivery they are yours, as is.
If you can be convinced that the speakers are undamaged (by close inspection and hooking them up and listening to them before you accept delivery) you might want to keep them. If not, don’t accept delivery. Send them back.
Always pay for online purchases with a credit card. If the guy doesn’t want to refund your money, set up a dispute with either Paypal or the bank that issued the credit card. The first question they will ask is, "Do you have possession of the speakers?"