I'd like to ask if there were any other workers that were also at Macdonalds that noticed Mr someguy leave and/or if he was there on the night of Mr. Deadnow's death death.

is Matt Mr. Someguy?

You ask his co-worker. The man shuffels his feet, scratches his nose and looks genuinly stressed during your coversation in which you learn Mr Someguy remained in the building.

I don't quite believe him...

You ask to look at the CCTV, but the man goes white and says that your not allowed before running off.

You ask for Mr Someguys first name. "It's Mattew," answers the officer.

Sorry I forgot to ping you. look at the two posts above! >.<

did anyone else live around Mr Deadnow?

Okay here is my theory mrs. Ladyperson was cheating on Mr. Deadnow with Mattew(Mr. Someguy). after mr. Deadnow fiered Mattew, him and Mrs. Ladyperson devised a plan to get revenge. so Mattew convinced Mrs. Ladyperson to help him kill Mr. Deadnow....

Did any of his neighbors have cameras that may have overlapped on to his property showing us even a glimpse? Or a traffic/street camera?

He had two other close neighboors:

~Ms Acrosstheroad- an elderly woman who hardly ever leaves her flat.
~Mr & Mrs Lotsofkids and their three children, dog and hamster- a loving family who adore animals.

If that's your answer message me privatly and i will tell you if your right