Can someone explain some things i experienced last game against the AI?

Background and details

AOE 2 HD Steam Edition using base game data set.

Started off as a 4 players vs 3 Moderate AI on arena. Went very poorly for us, the two flank players were slowly beaten back losing both of their bases and eventually a massive 3 direction assault came for my base where everyone now resided.

It was 5 hours in and the other players had to leave for various reasons, overheated laptop, computer freezing from too many units on screen etc.

So i was by myself against 3 AI, they had broken down the walls and had a massive army outside. Or at least so it seemed.

The issue below

The AIs didnt finish me they just sat there. I eventually got an army together at max pop to try to have a final battle but i just ended up cleaning all three of the armies up with hardly any resistance, i just mowed through them and they refused to resign and forced me to kill all of their units.

The AI let me win. Did we pass a time limit where afterwards it just sits there and dies?

I also seemed to research spies (2 enemy units left) SUPER QUICKLY. It almost seemed as if i had used some sort of cheat or exploit.