RVXoldtimer, lets hope that still holds true.  

The only concrete information announced was on June 14, 2018, is the following,...that US FDA is likely to support the filing and approval of an NDA depending on the success of BETonMACE.

https://www.resverlogix.com/investors/news?article=612

It does not specifically state that US participation is not required for the reason you stated, but I do recall it being said by DM at some point. 

Prior to that the following was announced on March 19, 2018, with intentions of US participation, but may rely on the existing BETonMACE data to file a US New Drug Application (NDA).

https://www.resverlogix.com/investors/news?article=596

Koo