Some would and others couldn't. Many teams can't afford to fly out American coaches to work with them. They have who they have and that's it. Even companies like Spring who do work with a lot of Intl. teams can't keep up with demand. My understanding is that they are only working with properly levelled teams this year. Where does that leave IO(C) 6 teams?
Look at Flyers. They have been working with Spring for years now, have several globes in IO6 and they were the first non-US team to get a globe in a Sr. division in 2016. How long have they been at it, and they have the resources and ability to work with outside coaches. They wanted to play with the big dogs and have been busting their butts for years now to do it. Many teams just can't do that due to costs.
Like I said, I hate the top 3 thing, but I don't think changing it right now will help. We need more equity. Honestly, I think the best we can do at the moment is bring in a minimum scoring to make finals, at least in the Intl divisions. That way, these teams still have the motivation to attend, are pushed to get better, but they're not being shut out completely by strong US (and maybe Canadian) programs. A lot of programs will see fair placements as something they will never attain and will just stop attending.