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Pardon my intrusion, but I cannot verify Molex's marketing specs either. 

this is what I think. 

This is an edge-coupled, embedded, differential waveguide geometry.

For Zdm to be 100 Ohms +/-10, and trace pitch = 0.500 mm with space, s =0.23 to trace, and height, h1 =0.10 mm above ground plane(=ref),  s/h1 = 2.3 then  I estimate Zo must be 100/1.6 = 62.5.

Yet with 0.100 mm PET Er= 3.4 , between any conductor and gnd plane, the I estimated Zo= 33 ohms. 

So I look forward to your results.  

  Tony  EE since 1975 , practising retirement

With 0.1mm thick PET (Kapton), between Aluminum foil shield and Cu traces, you have a waveguide and thus a controlled Zo It will be about 30 pF / sq.cm which like a high pass filter will shield the RF signals and provide low impedance Zo where the prop. delay time is greater or equal to the risetime. For short lengths or slower rsietime signals, Zo does not apply with T-line effects yet the shield now acts like an antenna to AM/FM signals and couples into Zo but not Zdm "iff" it is perfectly balanced.

Anecdotal: Alum. foil is lossy and will combust in a microwave oven with wrinkles but when flat is an excellent reflector.

I can estimate your DM impedance accurately from Zo from the gap ratios for DM/CM, so make sure Zo is accurate.

 On one page they call it a 90 ohm USB 3 cable and another page advertise it as a 100 Ohm HDMI cable.  The Engineering doc indicates 100 Ohms +/-10 for Zdm which with this geometry tells me Zo must be 100/1.6=62.5 yet I compute 33 Ohms.

The other thing of concern is if the shield is not terminated, there will be CM EMI coupling to the CM signals and any mismatch in the traces will translate into loss of signal integrity.  Anecdotal: I was delivering a custom designed Gantry for EM WPT measurements to U of T researchers and the Laptop USB would not communicate with an Arduino on a 1m cable if the 19V DC laptop charger was connected, yet when charger was disconnected, error-free and same when connected to a PE grounded PC tower on USB and this wasn't even USB3 signal rate.

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