Kyuuseishu ≪MESHIA≫~Isekai wo Sukutta Moto Yuusha ga Mamono no Afureru Genjitsu Sekai wo Musou Suru~ - Ch. 36 - Invitation

[lightingcloud]

not impossible, but why did her henchmen attack him directly instead of talking to/convincing him then?

In case you didn't notice, MC isn't really listening

 

[quanbe]

I thought the knight is Edelweiss.

Same for me

 

[Grikath]

not impossible, but why did her henchmen attack him directly instead of talking to/convincing him then?

Demons only acknowledge power, classic trope...
For her direct subordinates to even accept a "mere human" to be considered Worthy of her attention that human must be stronger than them.
No way around it.
And the only way to do that is to show strength at at least the same level as the subordinates in question. Which usually takes the form of combat, because that's the only way to gauge brain and brawn in equal measure.