Adequate decoupling / noise reduction for two accelerometers?
The datasheet describes device as very well noise immune one with ratiometric (to power supply) output from DC to 400Hz. So to read DC "ratio" well, try use 2+2+2=6 wire "drive" "sense" cable for 2 devices. At DC you are affected by ohmic, galvanic, thermoelectic forces, but not the radio.

-- Drive ---&gt;--*-----+----------------------------+
-- Sense ---&lt;--/     |                            |
                     |                            |
-- Sense ---&lt;----Device (of DC half bridge type),Device---&gt;---Sense--
                     |                            |
-- Sense ---&lt;--\     |                            |
-- Ground --&lt;--*-----+----------------------------+


All 3 sense wires should meet ratiometric input of ADC, say top goes to positive reference input of ADC, middle into positive input, bottom sense goes into 2 pins: negative reference (of balanced input) and negative pin of input.

Edit: Other thought. If there is movement on flexible cable, think about "triboelectricity". If cable friction, hit, vibration is an issue, then read specs about correct impedance of load. If this is high impedance, then add differential "line drivers" with current loop output and match a type of ADC to be "current ADC". Or better add small ADCs on board itself.