SIM not Valid after factory reset using a non-US SIM card

I bought an unlocked iPhone 5 at a US apple store. It worked fine for two years until factory-resetting it. Now, during the setup process I get a "SIM not valid" message. I tried an iTunes restore to no avail. I called Apple support and was escalated to two different "experts". I got two very different answers:

Expert 1: an unlocked iPhone can be used internationally but can only go through a factory reset with a US SIM card. Since you don't have one you will have to come back to the US, get an American SIM card, finish the setup process and then you can get back to using it internationally. There is nothing we can do here at Apple to bypass this procedure.

Expert 2: Our database shows that your phone is indeed unlocked and is available for use with an Israeli carrier (which is the carrier I am using now). Either the SIM card is defective or there is a problem with the hardware of the phone. Please ask for a replacement SIM card from your carrier and if this does not solve the problem you can send it to the US for repair. The repair will be costly.

Obviously neither of them is solving my problem. Is there another solution? Is it time to make the switch to an Android device?