Recover Highlights is only available for RAWs. If it’s available, it appears in the first edit section along with Auto Enhance and Clone.
It is also not available for ProRAW files, as they are not actually RAW files (despite the name, they do not contain RAW data).
If it’s a JPEG, then you can use Split Toning. If it’s a ProRAW, you might try Tone Map first to see if that helps or not with getting detail in the sky.