If Nick wins and Colorado law applies, Nick should win anti-SLAPP immunity on the negligent and intentional infliction of emotional distress claims. The judge already said they were shit but that summary judgement was premature before discovery. I don't know if Monty can voluntarily dismiss those claims and avoid the anti-SLAPP, but he should if possible because they're doomed.
You make a good argument on the conflict of laws issue that Monty actually should respond to it, although I would still consider it a rational strategic decision not to respond to it (unless he has already paid a retainer for the guy to make a response on his behalf), especially if his funds are limited.
I definitely agree on the IIED and NIED torts. These aren't going anywhere no matter what happens on the appeal, and if it does come back with SLAPP in play, he should amend to get rid of them. They're going to be dismissed anyway, and even if they weren't, it's almost a no-brainer that if he loses defamation, those aren't going to bail him out, and if he manages to win on defamation AND the IIED/NIED torts, the damages are almost certainly coterminous with the damages for defamation, that is, he isn't getting any more money out of it from those.
What's great about that scenario is that denial of anti-SLAPP immunity on the defamation claim would be immediately appealable, which I would wholeheartedly support Nick bankrolling.
I think that depends on to what extent and if the appeals panel adopts the procedural as well as the substantive aspects of the anti-SLAPP law. I
think they'd probably adopt it in full, if they did, but they might insist Minnesota rules about interlocutory appeals are a core interest enough to refuse to adopt the immediate appeal aspect of the law as it relates to Minnesota's ability to manage the internal relationship in its judiciary between trial and appellate courts. The closest thing I can think of to it is an Erie doctrine case called
Gasperini which I think kind of sowed chaos, but is so far as I know still good law. I'm not going to Shepardize it though.
That itself may be a compelling reason for the conflict analysis to favor the (lack of) Minnesota law, and is why the majority of federal courts that have addressed whether to use a state's anti-SLAPP law under an Erie analysis have declined to do so.
I know Erie and conflict of law are two different beasts, but they both exist to resolve disputes over which sets of laws courts use.
In any event, if Monty does respond he should very definitely argue along the lines you did, highlighting the difference between the Colorado and the Minnesota law and how Washington addressed the deficiencies of its original anti-SLAPP law by essentially cloning Colorado's.
It's at best persuasive authority, but even so, has the potential to be very persuasive.