Having a correct path of communication between the fop2 server and AMI is important, but it is not the only thing needed in order to send *correct* commands to Asterisk. I put emphasis in *correct*.
In general, for every command to work -except for hangup or record-, you have to configure an extension and context in the button definition that must match your dialplan, as set in asterisk's extensions.conf. Also, you need the "originate" permission in /etc/asterisk/manager.conf
If you want to troubleshot, you need to start fop2 with debug level 15 and then inspect the output when you try to originate a call, to start fop2 in debug mode you have to pass -X 15 to the startup command.. you can do something like this
killall fop2_server
cd /usr/local/fop2
script capture.log
./fop2_server.pl -X 15
(connect to fop2, try to originate/dial a call)
ctrl-C
exit
at this point you have a capture.log file to inspect.
My guess? You might have incorrect extenxion/context configured in your buttons, you might lack the originate permission in manager.conf.