Since this thread is now starting to become about improving your team, before you train rookies and invest in high level trainers, PLEASE build your arena. Large arenas are the hidden (but not so hidden) steroid on buzzerbeater for improvng your team. It is the primay source of income, and with a large income comes a good team full of good players that you can afford and make profit off of. A HIGH level trainer is not needed, and I'd say level 3 is quite satisfactory. I successfully trained a guard (who is now 56k salary) that played on the U-21 NT and I THINK the NT on my former team. Also, by investing heavily in the draft, how heavily are you talking? Improving your arena is much more important, since you can spend 40k a week and end up with some pretty crap players, but with arena improvements you can make more income as I said, and possibly buy the rookies yourself, where you have more "customization" and choices in a way.
I wouldn't really pay much attention to those notices. You sure can train one of those guys and ask the US NT owner or myself for some advice. If you get a good rookie with allstar potential or higher, go ahead and train them accordingly.