If it were me? No chance of letting them off the hook. I wouldn't buy boots and then let the company walk all over me with them. I suspect they are trying to delay you initiating a refund in 14 days which is your right by law for a mail-order (internet) purchase.
Some people prefer an easy life, and will accept this kind of rubbish, because of this retailers will try to make it more difficult to return things.
Usually you can leave bad feedback, write a scathing review, complain about the poor service, but when they maintain their own website that avenue is cut off completely and you're even more so at the mercy of their staff. This is why amazon ruined regular shopping because their primary selling point was a no questions asked returns policy. I worked in a shop selling televisions and we made it very difficult to return your stuff, we tried everything we could possibly think of to make it difficult and convince you to keep it. Every refund impacted our daily sales figures and that wasn't something we liked. In contrast I bought a TV for my parents which went faulty, amazon support immediately issued a collection, once they had collected it they refunded. No sending back for testing. No umming and ahhing. No trying to fob me off with the insurance provider.
I know very little about the law, but I would imagine that your rights significantly reduce after the initial 14 days, so I would research online what is available to you.
Now, if I buy something clearly repackaged as it was used and sent back, I will kick off. I have also accepted a 30% discount on a piece of equipment, I was initially ignored when I complained and received totally nonsensical email replies but in that instance I was buying through amazon so ultimately they stepped in and sorted it out but the seller definitely tried to avoid helping me.
There was one time I managed to get pc world to BEG ME to come in store to resolve an issue. Social media helped me there.
I would be miffed about it like you are. You shouldn't have to put up with shoddy quality.
(edit; seems I was a bit slow in writing my post lol)