I have a slightly different opinion. If You took the whole foglight out, or even just the lenses it obvious that it's made of few different materials. What we called a " unit" it was previously assembled into that unit. If it's not one piece, there must be the way to disassemble. I was watching some time before - how to repaint headlights inside on YouTube. And applied the same technique to open my cracked foglight as the Guys did to open Headlights. Heat. Only instead of oven I used heatgun to soften up the seals which are holding together all parts of foglight. Never thought of posting something here and don't have any pics of my job. But search YouTube, there is the whole detailed process how to open the headlights. I was searching how to DIY "Halo Rings" or "Angel Eyes" into my Ute. Back to the case.Having whole unit disassembled I cleaned and resprayed reflective backing with "mirror efect or mirror finish" spray can from Bunnings. Probably Rust-o-Leum product, then I sprayed just in case - "Engine Clear Top Coat" - heat resistant clear coat from 'SuperCheap Auto" by "Duplicolor" Then I gave all cracked glass a really good clean followed by filling up with epoxy two pack glue also from "Bunnings" By "Selleys" - "Ultra Clear Araldite" product designed to glue glass together. Finally used "Dremel" polishing attachment to smooth out glued pieces and the surface of whole lenses glass.All parts of foglight glued together with the silicone and some "sika-flex" ( I had leftover from some job). When completely cured - It's save to install that back. Still plenty of product I used left. Estimating I can fix the same way at least 10 craked foglight lenses. But I already had all of those. Never had to buy anything. But I'm guessing - it's the cheapest option. Sticky tape or other quick fix solutions doesn't count for me. Like using "Play-Doh" to seal the gasket.
Cheers Guys
