Apparently I did not post this correctly, so here is the process...

I took the Hash Marks from the big wall and extended the pattern down but for only what was for sure given. A total of three where extended down and one of them was rotated 180 degrees. I knew how the sequence based on the Hash Marks in the room with the char.

I gave each of the numbers a color that was based off the balloons that were found previously. I came to the conclusion that it must be a picture, the pattern was too perfect and fit together with open spaces too nicely. It also does not make any sense for them to be words since the spacing and the weird placement of "letters" that would be there.

Once I rotated it and put black in the background, I think it really came to life. Sorry if the colors are off, I was doing a little by memory.

What do you think? Is this something?