@salty There's actually three more rows and five spare 16A breakers! Which is why I understand even less why they didn't make use of the third phase at all...
I was about to say "I'm sure it all works and is in spec, but feels a little iffy" but actually, not really, the single 16A breaker is well undersized for the 7.1kW stovetop hooked up to it, which at 230V (because single phase) would be up to 30A. Let alone also connecting an oven, that would definitely need its own breaker and wire then.

