Given the political situation of the past dozen years, the dearth of section 7 cases shouldn't be too surprising.
Yes, the complaint could be amended by September 6, as the federal rules permit plaintiffs to amend their pleadings within 21 days of service. Both US/AA and the government agreed that Friday, Sept 6 would be the deadline to amend the complaint. Here is an article that mentions the agreement on the Sept 6 deadline:
http://aviationblog....tml/#more-17085
Good grief - you are really reaching with this one. Every federal judge has a "reputation" of encouraging settlement. Nearly every case filed in nearly every court in this country settles prior to trial. Perhaps this one will settle, but it won't be because you've discovered something unique about this judge.
Uhh, you're reading far more into routine deadlines than is warranted. The government has not indicated that it will amend its complaint by Friday. The deadline to file an amended complaint is this coming Friday.
This is one area where uninformed speculation is not necessary, since we have a recent government case on this issue: the US slot giveaway to Delta. The government made it fairly clear that about 55% of the slots was the maximum that an airline should be permitted to accumulate via a transaction, and thus, it would be reasonable to assume that new AA will have to give up the number of slots currently held by AA, so that new AA will hold the same 55%.
What's the risk to the Department of Justice if they lose the case? None. A little pride, perhaps, as all lawyers like winning cases that they bring. What's the risk to Doug Parker? If Parker wins, great. If he loses - it's all over. He won't have the network to survive and US won't have the revenues to pay its pilots (assuming they ever stop fighting each other and demand industry-average pay).