That's a pretty piss-poor reason for Denver to be considered geographically favorable.

The main advantage you get from geographical proximity is the fact that you can build closer networking opportunities to other businesses and entities in the area. (A secondary advantage is timezone alignment). Denver's not exactly close to any other major cities; by contrast, it's only a half day of travel between Chicago and the Northeast, and it's even possible to commute between NYC and Boston or DC for a day.

For siting a second major HQ, Denver is just too close to Seattle. You don't get the benefits of having people 3 hours ahead (and more aligned with Europe, for example). The marginal costs of extra travel time to Asia from the east coast versus the west coast just aren't going to be a major factor in determining whether or not travel can happen--your employees have already lost a day or two of travel. Move the site to the east coast, and now you can open up more travel opportunities because it's only a half-day (or less!) of travel.