I'm assuming that the FBI has access to Trump's tax documents. If so, the FBI is in an excellent position to consolidate Trump's tax data with his business dealings with Putin and his fellow Kremlin based oligarchs. Can't wait for their findings to see the light of day, but I'm wondering just how effective Trump can be at shutting down the FBI's efforts in this regard.
Things being really high stakes money-wise, that fact alone can have all things Trump take some really wild turns with surprising outcomes. This huge oil deal being one of them, for sure timing is everything and in this regard, it seems for Trump this deal is much too personally profitable to permanently shut down. It will, it has to come back around because there's too much $$$ involved and too much influence peddling by one of, if not THE strongest lobby in the nation. With Trump being of their ilk, it pretty much seals the deal.
Trump has this huge advantage of being POTUS in order to leverage his financial interests to heights unknown, so it's safe to assume that being who/what he is, he simply can't resist the temptation to side with his chosen SECSTATE Tillerson and his blatantly obvious connections with Big Oil. Of course, with Trump being somewhat restricted per his running his businesses he will do whatever he can to run his profit making schemes in the shadows of shell corps. and other such tools that cloaks his identity from exposure. It's an old tried and true game that he's been playing for decades and his being POTUS won't change a thing about it or him.