Lead path capture mandatory fields

Hello, 

i like to mandatory capture a closing reason and comment on a lead path when status is changed to closed. I could use key fields on path together with a validation rule to make it mandatory. But the key fields can be collapsed and user then will try hard to find the dropdown arrow to expand. Unfortunately there is no config possible for a specific path to have it show key fields default expanded. 

Does anybody have another idea how i could get this solved? 

I was thinking of maybee open up a modal to capture fields but could find no possibility to trigger this when the status is changed on the lead path.

Thanks for any ideas in advance.