Yea, but when the news broke the deal was way past that point. Probably just waiting on medicals, if that.
I did some research and not just MLB. Obviously this situation has happened many times. The common denominator was it was the off season, player was travelling, etc.
There were some cases where the GM called down to the player in the facility and said, heads up, this is what is going down.
It appears by all indication that when this trade news broke, it was pretty much a done deal. Especially considering less than an hour later is was confirmed as done and they had the social media posts ready to go.