I have had an adventure pack for, geez I don't even know. 6 years maybe? It has been very solid for me. I can't comment on the company as I haven't really had any interaction with them. I bought the pack, received it, and have never had to go back to them.
That being said, your after purchase experience is troubling. If you don't get any reply just file a charge dispute with your credit card company. That will get their attention.
I'm hesistant to do any alterations to repair the pack in case I get an exchange, but it needs to be fixed.
Yea honestly i wouldnt waste any more time. i would send one more email like monday morning. Explain you expect to hear from them by the end of the day or you will have to file a dispute with the CC company. If not call in the dispute. That will get the ball rolling.
Once the CC company gets all of the information they will contact the seller. At that point the seller has to deal with it, or else they will be out the money and you will have a free pack.
It's sad to have to do this, but I have done it in the past with small sellers who would simply not respond post sale.