Mmm that seems like it might be the better option where did you get the barrel connector?
Also are you using the same PID? Just connect two of the cables?
Could this work?
That one comes with 3 cables. On the diagram it shows you how to connect it to the PID. you need to connect the 3 cables and then change it over to the RTD thermocouple in the settings.
I bought from NDE in cape town (https://www.nde.co.za/) to be exact https://www.nde.co.za/categories/bsp-fittings . just google BSP fittings and you should find a supplier in PTA. I built my entire system with a assortment of Barrel's and nipples.
I dont think what you linked will work. You need a RTD P100 with 3 wires. I dont know enough to know how you would hook it up with either 2 or 4 wires.