You sound like you have the exact problem i had, i fixed the hook in by copying the export.lua file and the viacom folder from the C:\Users\yourname\Saved Games\DCS.openbeta\scripts folder to the C:\Users\yourname\Saved Games\DCS\Scripts.
Vaicom now works but still doesnt see the module, but this doesnt really matter if you set up the profile in voice attack to use the same hat switch buttons or whatever you want to use as the comm buttons in DCS. Not sure if this is needed but it seems to work for me. (open the vaicom profile by the box with a pencil inside at the top right, go to the 'push to talk' list and double click the items in the button column, assign tx1, 2, 3, 4 to your hat or skip 4 and assign 6 to use your custom commands)
for info, I use SRS too, i disabled the two ptions to integrate it and use the PTT on the MP page in vaicom and also disabled the setting in SRS to use comm switches as PTT and just configured a separate PTT button for SRS to keep it simple too.