That’s because they sell an “isolator module” to solve this… Now it just so happens that the capacitors work for isolating the EC from pH, I don’t know if it’s a good solution for every possibility. I do not have the isolator module so I couldn’t say how well it works compared to the capacitor hack.
Are both probes in the same physical location in the solution? The EC can be affected by boundary conditions. Don’t mount it too close to the sidewall of the container. The “range” can be different for the SEN0244 probe compared to your reference probe depending on the sensor design.