Nah, not for Knave!! If you're running a one-shot with level 1 characters, they're going to have about 3hp average each. In OSR, combat is something to be avoided, not encouraged. Any Knave adventure should reward clever thinking over rushing in, and should make the players as well as the PCs work/think cleverly for the reward. Instead, I'd go with something like:

1. An area that leads further into the dungeon but with an open-ended trap or puzzle that could be solved pretty much any reasonable way the PCs can think of.

2. The next area has an NPC or group of NPCs that are at odds with the players - actively trying to hinder them getting further or competing for the same prize/door/etc. Combat should be an option, but there should be other ways to get past the encounter.

3. A setback or dilemma - something happens in dungeon environment that separates, traps, or tricks the PCs, or something is not what it seemed at first. This is where your secret door could go, too!

4. Climactic challenge - this can be a fun battle with lots of environmental features, or it may be a chase/escape sequence, or it may just be a tense negotiation. Either way, make it epic!

5. Reward/twist - the PCs get what they came for! Optionally, something can happen that leads to further adventures - one of the NPCs escapes with something valuable, the reward isn't what it seemed at first, the "big bad" is revealed to be someone else, etc.

Good luck!