
I tried Grafu Hard mode today with all my new information from this thread.
I put random numbers in till i got the correct number.
Decided to write the correct numbers at Sequence #5 request onwards to see if I could work out how they got it.
The last 5 correct numbers were 5,4,5,4,3
And then a lightbulb moment 
When it asks for the first Sequence number, you have to look for Number 1 as the last number and then you just type the number in front of it. In this case 51. So the first correct sequence number is a 5
You then look for the number 2 as the last number. In this case its 12. So you enter 1 as the next correct answer
etc.
I now understand why the above guide gave a second jumbled sequence of numbers, (my initial query) he was merely putting all the numbers in order sorted 1-9 going by the second number. This is the part that confused me.
Now I am happy 
So by putting all the numbers in their correct order first 1-9 by the 2nd digit in each sequence
you will get 51 12 53 74 55 46 57 48 39
You can then just type the first digit of each for the correct sequence to be entered into the box. 5,1,5,7,5,4,5,4,3
--
So, in the guide instead of having "Now you look on the second digit cos it tells you when first one should be used"
Replace it with - "Put all the numbers in order 1 to 9 by the 2nd digit"
and then after your correct sequence type "Now select the first number of each for the correct numbers to enter"
Great guide btw, thankyou for posting it up
--- Title spoiler
Some Extra info, While being attacked after entering the wrong number, every so often a Freakshow sidekick will appear in the attacking group. When you kill it 3 times i think it was, you get a freakshow Title. So it looks like putting incorrect numbers in worked out to be a plus for me
. I'm not sure if the sidekick only appears at that point for the title.
Also, it drops this

After rightclicking the Potion and using it on the Keycard it merely highlights the 2nd digit on the card with the extra info I was missing in my query of putting the numbers in order by the 2nd number. If your group is having trouble with the timer you can use this to reset for another hour.
" I can't make this any clearer"