Hope you can get new or resoled boots soon. Regardless of diabetes, PPE footwear should be suitable for purpose. I'd get my union onto it.
In the meantime, for your own comfort, you might want to consider wearing waterproof socks - Sealskinz are the best know brand in UK. Cheaper than new boots for now.
Again, not an ideal soloution, but like many people who compete in mountain marathons, I carry dry socks to wear inside plastic bags inside wet shoes overnight, to avoid need to carry spare shoes.