Spotted your thread back in January and was hoping for someone to come in with a solution as I'm no expert when it comes to editing scripts and the like. That said I did find a solution thanks to Helios.
In short I used Helios as the interface to set up the viewports to export the the left and right DDI's and the AMPCD to the winwing displays (as apposed to using simapp) but also set it up to export the UFC within the unviewable space on one of the winwing monitors having watched this short tutorial on YouTube:
Rather than the use the generic left/right/centre MFD viewports described in the video I did use the F18 specific ones as that was the only place I could find the UFC. A screenshot of the the helios profile I setup is attached - the small monitors are the winwing MFD's and you should be able to spot the smaller render of the UFC on the right hand small monitor at the top.
Once done, just fired up DCS as usual with TrackIR and simapp running in the background as usual, selected Helios in the monitors option and was very pleased to find that once in the alt+F1 HUD only view that the UFC was fully functional.
Hopefully helpful