I have seen the record for Wilhelm after finding your other tread. Wilhelm was born from father Wilhelm and mother Theresia (i believe it's) Ahatz in Rabenhutte No. 1, not in 1877,but in 1880 (14. of august). Since there is no other Wilhelm from 1870-1880, it should be the one. And his parents were Joseph and Anne Marie from previous post. Theresia's father was Franz and mother also Theresia, born (i think it is) Sauhridl. They were from Wallern (Volary) No. 64. The midwife was Clara Gubitsch and the priest Mathias Schulistack.The godfather was Pius Kolmberger and godmother some Rosalia. I couldn't find Franz from Wilhelm yet, but if Wilhelm jr. was his brother, than those are your ancestors.
https://digi.ceskearchivy.cz/DA?lang=cs&menu=3&id=37... When you open the book, go to image 135. The handwriting is pretty clear so you'll have no problem finding Wilhelm Robl.