Click on Highcharts pie rendering border although legend item click is disabled

Setting the series states options is a solution to your issue.

Demo: https://jsfiddle.net/BlackLabel/w7jyr2zh/

states: {
    hover: {
        enabled: false
    },
    inactive: {
        enabled: false
    }
}

API: https://api.highcharts.com/highcharts/series.pie.states.inactive