I checked a list on the Cast Portal of "Authorized Off-Site Disney Ticket Sales Locations". This is a list of all companies in the Orlando area which are authorized to sell tickets or vouchers for tickets and lists about 90 names. I cannot publish the list as it clearly states it is not for public release.
That name does not show up on the list.
I also looked at their web site and the prices are impossibly low. Normally getting a 10% discount is good.
Their site does not provide any address or way to order except by phone. They do not show any "About us" or any privacy policy.
And a "whois" check showed they just registered the domain name this month.
I would strongly recommend against using them!