Well, it appears that the crack did not occur at that shop. Maybe the tow truck put to much of a "bend" in the car when hoisting it onto the flatbed, if it was a flatbed tow truck. Or when it was on the hook.
It sounds like you are going to be pretty well taken care of. If it were me and you have the leeway to do so, I would go with this. Ask your insurance company and/or Safelite, if they can get the windshield from (as stated below) Bob's Classic Auto Glass (1-800-624-2130). They have a brand new windshield for a '58-'60 T-bird in three different styles:
Green w/blue shaded band across the top
They are all the same price: $485.00 plus shipping. The company is in Eugene OR, but they have a warehouse outside LA, which could save you a hundred bucks in shipping costs. Call them.
They will be getting a windshield that you will know is really made for your '60 Tbird, and you have the choice of styles, depending on what it is now. Here is what the VTCI Official Factory Specifications (OFS) says about '60 windshields.