Predicting accurate time of local sunrise in mountainous area?
The PeakFinder app1 can do most of what you're looking for.  It's available for Android and IOS as well as through a web browser.  The app shows the paths across the sky for both the sun and moon2 and displays rise/set times taking into account the local topography and viewpoint elevation3.  At least the Android version works without a network connection (nice for hiking).  IIRC, it uses SRTM data4 for elevations so it's not super-accurate but does a good job over all.

I plugged in the location, elevation (ground + 1m), and date you gave and got sunrise at 05:09 local time, reaching the ridgeline at 08:37 local time.  Here's a link to the page; screenshot is below.

1 I'm not affiliated with PeakFinder, just a satisfied user.

2 If using a web browser, click on the "sun" and "moon" icons on the page's toolbar.

3 It also shows what the surrounding terrain looks like and the names of visible peaks.

4 As does OpenStreetMap, IIRC.


Source: Cropped screenshot of PeakFinder site