Back in the day of O Levels one of my teachers used to say, "pray for a hard paper" (RC school) because half of the students taking it panic, that gives you an advantage if you don't panic.
Sorry that would have been more useful yesterday.
The people marking the paper will try to give credit for anything and everything they can.
OCR know there is a problem.
Message to your DDs and DSs
You do not need GCSE CS to study it at A Level, in fact somethings you learned at GCSE will have to discard. Eg logic gates. For GCSE you learned about AND, OR and NOT - at A Level you will use NAND XOR and NOR gates.
If you want to prepare for A Level CS learn binary and logic. Not just logic gates but do logic puzzles as well.
Link to making circuits
https://logic.ly/demo/
You have had a bad experience, you have survived it and you can, if you wish, still achieve CS A level.