I attached a demo map with something you can use. Note that it's inefficient and certainly not the best way of going about this, however, it gets the job done and if your map isn't too crazy it should work.
How to use:
In the Show Hide Creep Camp Indicators trigger you set the variable CampRegion = Whichever Region you want to create a Creep Camp Indicator around. Then you immediately run the Create Creep Camp Indicator trigger after it.
In the map I created 2 Regions, CreepCamp1 and CreepCamp2, which I then created Indicators for using the instructions above.