What I can say though is that Zachery Group is an absolutely top end engineering and construction company and is headquartered in Texas. I'd be ticked off if they were left off the bidders short list.
Two mega companies that I have a lot of respect for wrt handling large projects on spec, on time and on budget are Zachery and Bechtel. High end quality controls and project management. In addition, they can flat slam resources into a project when required to meet tight timelines. I've worked with both of these companies.
Yeah, makes me curious why not hire local...