These issue could have easily been planned for. They get constant updates on the number of units sold by location. It does not take a "special" kind of math to determine that your server capacity is significantly lower than your pre-order quantity.
On top of that you are blaming the server throttle on an "instanced" duty finder issue? Seriously!? If that is truely the case then paying for more bandwidth and instanced servers is the only solution. There is no other way you will ever be able to get all of you player base in otherwise.
The apology is weak and lacks real information with a direction on how it will be fixed or a time line. Reading between the lines on that one only indicates they are weary of making a commitment they are unwilling or unable to make. Pony up the Cash SE, you have spent millions on getting the game to this point, don't blow it now!