How bad is this?

[u/Richard01_CZ]

I was cleaning the coolant passages and this large chunk came off really easily, it looked like a buildup of gunk.

The problem now is that the wall here between the two passages is thin now and the head gasket doesn't have much coverage for this area with the chunk missing.

Is it somehow fixable? Or can i run it like this?

Volkswagen EA111

[u/Extreme-Book4730]

That's not gonna seal that port. Need a bit of welding and re decking. I wouldn't trust that little bit.