You don’t need to prove you contracted it at work, you just need to prove that being compelled go to work including traveling was the most likely cause and was

You don’t need to prove you contracted it at work, you just need to prove that being compelled go to work including traveling was the most likely cause and was against the directive of the local government and medical experts which will be very easy to do so. Civil court has very different burden of proof and if it goes to trial the jury would nearly certainly vote in favor of the plaintiffs. If they will get sued they will settle and settle fast.