The UR for PredictionIO was last tested on PIO 0.12.1. We have moved it to our next-gen ML Server called Harness.
If you want to use it with PIO 0.14.0 you should make sure the build.sbt of the UR has the same deps as the build.sbt for PIO. In otehr words make sure the version numbers match. The UR in any flavor requires Elasticsearch 5.x, ES 6.x will not work.
In due time we’ll go back and get it upgraded for PIO 0.14.0. If you are in a hurry, you can try upgrading yourself or use PIO 0.12.1.
Not sure this is the root of your problem but will need to be addressed in any case.