We know that Yu Darvish met with Theo Epstein and Jed Hoyer in Dallas Monday night. And we know this, in part, because Darvish himself confirmed the meeting.
There’s a bit more information out there about this meeting. Some of it comes from this Nikkan Sports article, but when run through Google Translate, the usual fractured English comes up. One thing the translation did appear to note is that Darvish’s agent was also part of the meeting; it also noted that the meeting was at Darvish’s home in the Dallas area. The Google translation of the final paragraph of that article reads as follows:
The forces also prepared a familiar jersey number "11" for Darvish.