exec reboot - script not working on Fortimanager 5.0 Adom against FortiOS 5.0.X

I'm having a problem getting this simple exec reboot script to work in my Fortimanager 5.0 Adom. The FM is running 5.0.10 and Fortigates range from 5.0.9-5.0.12. I can't upgrade to 5.2 or 5.4 yet because I have 120 FGT running 4.3.18 but am in the process of upgrading those. The reboot script does work in my 4.3 adom. Has anyone run into this problem? Fortinet TAC is just saying it is a known bug and will be fixed in 5.4.1. This is such a simple script is really should work. I need the ability to reboot multiple Firewalls all at once.  Does anyone out there have this same issue or is working for you? I have 450 Firewalls managed by this FM. Thanks in advance.