If I remember correctly, this glitch is usually caused by upgrading your version of the hack (specifically, from v1.3 to above I believe it was?) and continuing using the same SRAM file. The reason for this is because at some point the location that the egg collection and void door completion data was moved to avoid conflicts that caused other glitches.
I think it can also be caused by buying the spacesuit before viewing the credits.
You could try getting a working save file from someone else, or try playing through the game/all the castle levels/Bowser's Castle again to see if that works. If neither of those things work/you can't be bothered, then either way all you're missing out on is the credits.
May we meet again outside the battlefield.