Hey Raf;
I don't know Nigma hortensis, but considering only the three species present in Germany, I would prefer Nigma flavescens. On picture 5 one could imagine the tubercels on the chelicerae and on picture 3 picture I 'see' the twist in the embolus. Each of these two characteristics would be enough for identification (at least between the three species present in Germany), but both are a little unclear to see.
I'm curious for other opinions.
Greetings,
Clemens