Time to reprofile the edge. Your brother in law would probably benefit from a guided system. Some like the Lansky are not too expensive and can do even super abrasive steels with the diamond stones pretty easily. The base will sharpen these too but not nearly as quickly. Also the diamond stones do well with water not oil. Oil is too messy for me. Edge pro is good but more expensive.
I have an Edge Pro and I am going to take it home and fix it for him. He is a rather competent with tools, so I didn't think it was anything he did. This knife had never been sharpened. It just seemed odd to me.
sure looks like it went through a pull-through sharpener to me.
you can tell from the grind line that is stretching cross-wise along the edge and where the piece of metal has cleanly chipped-off
i know because i have been sharpening my cheapo kitchen knives this way for years before learning about knife steels and the proper tools/way of sharpening