If you're only using one city (instead of dynamically finding cities that belong to a side), you can use this as a quick method to determine if one side has more groups nearby than the other.

Ex. using East and West

//-- Define necessary information
_position = getPos player; //-- Town pos
_distance = 500; //-- Distance to check for groups

//-- Get nearby west groups
_westInf = count ([_position, _distance, ["WEST","entity"]] call ALIVE_fnc_getNearProfiles);
_westVeh = count ([_position, _distance, ["WEST","vehicle"]] call ALIVE_fnc_getNearProfiles);
_west = _westInf + _westVeh;

//-- Get nearby east groups
_eastInf = count ([_position, _distance, ["EAST","entity"]] call ALIVE_fnc_getNearProfiles);
_eastVeh = count ([_position, _distance, ["EAST","vehicle"]] call ALIVE_fnc_getNearProfiles);
_east = _eastInf + _eastVeh;

if (_west > _east) then {hint "West is in control of the area"} else {hint "East is in control of the area"};

It's possible but it'll require a bit more work to implement (can see method in action when using intel tablet and observing objective occupation).

I'm pretty sure there is an easier way to do this but I'm lazy too look for it atm so.. this should work. Note that this will be a bit more heavy on the performance.

(I also made a typo in the code from the above post, so if you use that, copy it again)

Put this inside a function and call it (Must be called on the server).
It will return a position that is occupied by the enemy force if any exists, otherwise it will return nil
You can call it by doing

_position = ["WEST","EAST",500] call functionname;

With
"WEST" being the friendly side
"EAST" being the enemy side
500 being the distance to check for nearby groups

private ["_chosenPosition"];
params [
	["_friendlySide","WEST"],
	["_enemySide","EAST"],
	["_distance",500]
];

_objectives = [];
{
	_side = _x;

	{
		_opcom = _x;
		_opcomSide = [_opcom,"side"] call ALiVE_fnc_hashGet;

		if (_opcomSide == _side) then {
			_objectives pushBack ([_opcom,"objectives"] call ALiVE_fnc_hashGet);
		};
	} forEach OPCOM_instances;
} forEach [_enemySide,_friendlySide];

for "_x" from 0 to (count _objectives - 1) do {
	_objective = _objectives call BIS_fnc_selectRandom;
	_objectives = _objectives - [_objective];
	_pos = [_objective,"center"] call ALiVE_fnc_hashGet;

	//-- Get nearby west groups
	_friendlyInf = count ([_pos, _distance, [_friendlySide,"entity"]] call ALIVE_fnc_getNearProfiles);
	_friendlyVeh = count ([_pos, _distance, [_friendlySide,"vehicle"]] call ALIVE_fnc_getNearProfiles);
	_friendly = _friendlyInf + _friendlyVeh;

	//-- Get nearby east groups
	_enemyInf = count ([_pos, _distance, [_enemySide,"entity"]] call ALIVE_fnc_getNearProfiles);
	_enemyVeh = count ([_pos, _distance, [_enemySide,"vehicle"]] call ALIVE_fnc_getNearProfiles);
	_enemy = _enemyInf + _enemyVeh;

	if (_friendly < enemy) exitWith {_chosenPosition = _pos};
};

_chosenPosition