To match the metrics with the sets of params:

'paramGrid' is a list of Param maps; 'avgMetrics' is a list of metrics. These 2 lists have the same order, so you can just zip them together:

zip(cvModel.avgMetrics, paramGrid)

To find the best set of params:

If you have a CrossValidatorModel (after fitting a CrossValidator), then you can get the best model from the field called bestModel. You can then use extractParamMap to get the best model's parameters:

bestPipeline = cvModel.bestModel
bestLRModel = bestPipeline.stages[2]
bestParams = bestLRModel.extractParamMap()