PDI Over Intermediary Cable - Sensor Track

I'm planning a shelf layout around a roughly 14'x14' room.  When I finished the room I routed 3 sets of wire drops inside the walls to locations on 3 separate walls at the level of the intended shelf from a corner of the room down low where the control panel is intended to be.  Not knowing what I'd need I ran quite an expensive collection of copper to try to cover myself for power to 2 tracks (even using twisted 12 or 14 gauge in case I wanted to add DCS in a "star" later) accessories and switches.  Among the various cables at each of the 3 drops are 2 separate 18 gauge solid copper 6 conductor cables.  

I'm now thinking about how I can incorporate sensor tracks into this shelf layout.  They weren't out when I did all this wiring (year 2000 - SOMEDAY I might actually get this layout built) so running PDI cables in the wall obviously didn't happen.   I already have an LCS SER2, WiFi and STM2 modules.  Obviously these would be located at the control box in the corner.  The question I have is whether there is a way to utilize the wiring (like the 6 conductor 18 gauge wires) I have hidden in the walls to connect the PDI signal from the control box set of daisy chained LCS modules to sensor tracks on the shelf near the 3 places I've got the cabling already at?  Could I take a PDI cable, cut it in two and splice each end on one of the cables behind the walls?  Or could I hide a SER2 on the shelf layout connected to a sensor track and connect the data and common to the SER2 in the chain with the other LCS modules at the control center?  (I'm guessing SER2s can't be used to bridge LCS devices in this way but I hope somebody on the forum knows for sure one way or the other.)  Trying to route a PDI cable from the control panel through the walls with all the rest of the wiring isn't something I can do know without some drywall repair I'd like to avoid.