Next thing to do is:
Launch DRM, then go to settings after you click on the bar "Replay" and put a tick on Log actions to log.txt it gives us a capability to generate a log of the replay. And you may remove a tick on Time relative to creep spawn(So, you wont have a problem with divergence in time of creeps spawn).

So what do we do as a next thing? We download a replay and open it with DRM, then we go to Action log( You may look at my previous topic about how to use DRM). Let's suppose you got a couple of supsicous moments with approximatly time stamps. And you chosse a player right there, and look for what he selected(clicked) in what time you had suspicons on: •Time stamp Nickname 0x19: Select Subgroup: [Heres an image + name of unit] 0x00007645003238E28 . And for example you see a player(Map hacker) selected subgroup void. In other words, he clicked on a void. Then you go to replay and check what kind of a click it was. In WC3 when you watching the replay , you may press CTRL+C so you may see everything what that player is clicked on. Simple as that.
The tools which can help you in finding a maphacker:
Replay Seeker - Very useful tool to check a certain time stamps, so you no need to wait that long. And you can set a certain time in Replay Seeker and Alt+tab to keep doing your staff, when the needed time will be ready you will get a signal/notification.
FCD(Fog Click Detector) - You should be already knowing that this tool is extreamlly glitched(i will add kind of glitches later, when i got a time). But you may use it to get a fog clicks, then you go DRM and check those clicks were they legit or not. But you never can make a conclsuion whether player a hacker or not based on only FCD.
AutoC(Auto-Click Script) : As i stated before when you check a replay you may press CTRL+C to see what player is clicking on. So this tool makes it more easy, you no need to press CTRL+C instead of it you just install this sctript, and it will do it for you automatically. You just turn on or off it with F8.
As a conclusion, i would say when you dont have any time stamps, but you sure he is using map hack, you have to work with his log like for 15-20 min by checking his click properly.