Halo 2 Anniversary Infection Game Type issue

Hi!
So recently I’ve tried to make an infection Game Type but it seems that it doesn’t work properly or I’m missing something, I don’t know. I would really appreciate your help.
My idea was to have only one infected player and the rest to be survivors and everyone has only 1 life, no respawns. So if the infected gets killed, the survivors win and if the infected kills all the survivor he/she wins.
I’ve been testing this game type with 4 controllers in one console, I have an Xbox One X (just in case this issue has something to do with what Xbox I have). If the infected gets killed without him/her killing any survivor, the rounds ends and it says “Survivor Victory” and if the infected kills all 3 survivors, the round ends and says “Infected victory”.
Until here everything looks good, however weird things started to happen. If the infected kills 2 survivors and the last man standing kills the infected the round ends and says “Infected victory” wich doesn’t seem right, but that’s not the worst problem, if the infected kills only 1 survivor and then gets killed the round won’t end, and because everyone has only one life including the infected, we’ll you’re stuck until the time runs out or one of the 2 remaining survivors decides to suicide, in wich case the round will end and say “Infected Victory” again.
So I need help fixing this, please, in the general settings I put that everyone has 1 life, of course. Am I missing any detail on the settings or in the map? Is it a glitch? Can it be fixed? Please I would like to know. Also if you have a game type that meets the specifications I’ve written above without this issue, could you please share it with me or tell me wich settings you used, please?
Thank you all!