It is not pre-fit and manufacturer won't respond! - Dreadtec Tikka T3 Pre-Fit Advanced Composite Threaded Rifle Barrel

I purchased this barrel 3 months ago. It seemed like a good alternative to a Proof barrel. In theory, the company might have a unique product, but the quality control and customer service are SOOOO bad, that it is not worth the risk. It has been at my gunmith for 3 months. It says "Tikka pre-fit" but it needs a nut like a Savage 110 to install the barrel. It also says it requires a thread protector but didn't come with one. It took 3 months to get a response and all they said is they are available on the website. This barrel is for 223 Wylde, yet the thread pattern is for 5/8"x24 instead of 1/2"x28. Strange that they would do something so wonky and not provide it when they say it is required. BTW, I can't find it on their site. It appears that they fixed the wonky barrel nut threading to 1/2"x28 and that is available, but nothing for the barrel I bought.
BTW, they have a link that says "Dealers." Turns out Optics Planet is the ONLY dealer... So now my Tikka is torn apart and I can't get the barrel nut to finish putting it back together and no response from the manufacturer. What a joke!