I do feel bad because I have been in that position as an artist, where I made a lot of graphics for a game that just didn't have any progress made on the programming side. And I understand wanting to show off your concept art and what the game was planned to be over what actually happened.
With that said, at the very least you should have the correct controls on your itch page. Space isn't shoot, it's mouse button, and aiming is with the mouse as well which isn't mentioned. Which to me sounds like less an issue with the programmers running out of time and more a lack of communication - did the artists make the controls graphic at the end without knowing how far the game had come along? Or did you make the controls graphic at the start of the month without being prepared to pivot if the game's controls changed?
Also, a lesson to all game jam artists - learn a bit of the game engine you're using, that way you can at least put your background graphics directly into the game and have something on the screen.