Loosing the Stereo field when checking my mix in Mono - Abelton Live

[PTB]

I recorded several takes of strings from an external mono string machine into Abelton Live. Each are panned differently.

On each channel I have Abelton's compressor for side chaining, an SSL E-Channel Mono plugin for EQ, and Abelton's Utility plugin last in the chain for gain automation. The Width was originally set to 100% but I realized that since it's a mono track there is nothing in the stereo field to push further out so now this is set to 0% and only the Phz-R button is enabled.

I'm monitoring through the Dangerous D-Box and my master channel has the PSP Stereo Analyzer plugin. I notice when I play my track that the PSP plugin shows very little stereo imaging. The display mostly shows movement vertically in the center. When I hit the mono button on the D-Box everything remains in tact with just a slight reduction in volume - so at this point the track is mono compatable.

When I turn off the Utility plugin on the string channels and check the PSP - I immediately get a much wider stereo field - something that looks pretty normal BUT... when I hit the mono button on the D-Box the tracks totally disappear. I've tried a lot of different configuration settings on the Utility plugin and routing the audio but with no avail. What am I doing wrong or missing?

Would really appreciate the help!
Thanks!!!

[Meow]

Why are you flipping the phase?

[PTB]

I'm not intending to just trying different settings.

I've tried enabling both - nothing
I've tried disabling both - nothing
Just Phz-L - same issue

[PTB]

If I disable both Phz-L and Phz-R and hit the mono button I get a flat line going from left to right on the PSP. I have to have one of them selected to hear anything.

[PTB]

I have other tracks in the mix that have the same exact plugins and there isn't an issue when going from stereo-mono so I'm thinking it has to do with the recording stage. With that, if I recorded the strings with a mono (TS -->TS) cable but it's a polyphonic instrument - can this be causing the issue? If so, is there anything I can do now to correct it?