I'm either blind or something but I can't find the keywordtool.io tool in my seo tools connectors.
Or is there another way to just use google's api for getting keyword volumes on given kws?
Have you looked in the Manager? 
I would have if I knew where that was. I think my version was old 7.0. Installed new version but can't seo tools to show up at all right now after updating to 8. it's enabled but not showing up hrm.
works now, updated.. had to repair then found it