Extremely doubtful that JT would have had any foreknowledge. The Federal government has only ever given Bombardier either direct subsidies for specific programs in research and development or for employment development purposes or straight out commercial (even at incredibly low rates) loans. neither of these entitled them to any say or insight into the operation of the corporation. According to reports here in Montreal, there were rumours of these talks for months in the industry insiders world, so the discussions apparently pre-date the Boeing fracas (in fact, if the rumours came to the ears of Boeing, perhaps it explains why they did what they did: get your punches in while you still can, type of thing). However, the Federal civil service has problems collating, analyzing and briefing their political masters on actual facts that have occurred. To keep track and inform them of rumours even industry insiders couldn't confirm is well beyond their capacity.
The Quebec government, on the other hand, was invested into the C-Series for 49% and, as a result here, have been diluted to 19% (16%?), so they would have had to be informed and agree to the operation in advance in view of their dilution. They made, to my mind, the right call. Better 19% of a large pie than 49% of a small one.
If, as reported, the discussions pre-date Boeing's action, then I would agree that avoiding tariff was not Airbus' prime motivation in acquiring a stake in the C-Series. Again, to my mind, a greater motivation would have been to acquire the next level of product, just below the sizes made by Airbus, to have a more complete offering, while in the long term keeping any attempt (by Bombardier) to go into their actual size market. Building in the US (which Airbus already does because they know that it is always easier to sell to the Americans if you can claim that you make it there) and as result avoiding the import tariff is just a bonus resulting from the recent actions of Boeing.
Moreover, I don't think this will be a problem for Trump: He'll simply claim that making the plane in Alabama instead of Canada just proves that he cares for American work and that only when you build in America can you really be competitive on price, as American workers are just the best and most efficient in the world; then he will claim that if his administration had not imposed tariff on "cheating" Canadians, the work would not have come to the US, where it belong by birthright - and claim another win (you'll be sick of winning!).
