Extended ACLs Not Always Being Inherited
[First of all, it seem your SUIG bit is lost (I'd expect a "flags: -s-" in the getfacl output). However, that's not what's causing the issue here.]
It seems that the report generator not only creates the file with a 027 umask, but also does an explicit chmod() on the file. When it does that, the POSIX ACL mask is lost.
Try the following (as root):
touch /opt/reports/testfile.txt
getfacl /opt/reports/testfile.txt
chmod 640 /opt/reports/testfile.txt
getfacl /opt/reports/testfile.txt
It seems the explicit chmod() spoils things.