I've been trying to create a more realistic TM4 audio, with the correct higher pitch, but when using Audacity, whenever i adjust the pitch, it effects the overall time, thus creating a looping issue, if anyone could help, it would be greatly appreciated.

You will need to cut the source audio into loopable segments for wail, yelp, priority, etc.

Step two would be to apply your pitch modifier or filter (for ex: to kill background noise) onto the single loop of sound. Apply the filter and test if the audio still loops smoothly. If it does, then you're good to go. If it doesnt, try copying the audio segment a few times so that it has 3 or 4 segments. Re-cut the audio out from this segment and test some more if it loops right.