OK, so the deadline is upon me and I don’t have time to debug this anymore, What I found was that there is a Speedtree shader node that gives color variation to the plants/Trees. This is causing some problem when used with the Foliage tools and make everything render black. Tested compiling in different machines, the problem always shows the same.I did disable that node and problem solved.
Not sure if it is Epic bug or Spreedtree company, but there you have it if someone finds the same problem.