They are still investigating the problem. I shared the info needed to convince them that there is a bug.
By the way, I found a workaround. You can run Fluent from the terminal (any version) by enforcing INTEL MPI 2018, which is the version with better performance. You can use the following syntax.
'fluent 3ddp -t24 -mpi=intel2018'
3ddp= 3D with double precision
t24= number of cores