The 4th Symphony full score does exist at NYPL. I saw a version of it years ago, but it wasn't in Weigl's hand; it was a WPA copyist edition from the Fleischer Collection. I remember thinking it may have been unfinished because there was something odd about it. The question remains if the holograph at the library is truly complete. I will try to find out.
The Cello Concerto was recorded earlier this month in Germany. It will be issued along with other concertos by Gal, Reizenstein, Castelnuovo-Tedesco and Goldschmidt as a collection of works by suppressed composers.