Can force firstperson, but can't get out of it? [UNANSWERED]

You have a typo:

if v.CameraMode == Enum.CameraMode.LockFistPerson then

You missed the 'r' in "First".

(The rest of this post is relevant even if that typo wasn't in your original script).

Sometimes Roblox won't tell you about an error. In that case, it's good to employ "print" debugging -- add print statements throughout your code (that is, the area of the code you are debugging) to figure out exactly what's running (deleting them when you fix the bug, of course). If you need to test it online, don't forget that you can read what the print statements say in the Developer Console (press F9 to open it).

ex, I might debug it like this:

--Sorry for bad spacing; that's ScriptingHelpers' spaces mixed with my tabs
function onCall(plr, message)
	--rest of onCall here
	print(plr, "chatted", message) --prove that the code execution got to this point
        if message:sub(1, 13):lower() == ":thirdperson " then
		print(plr, "chatted thirdperson") --prove that the if statement worked
            local victim = findTargets(plr, message:sub(14))
		print(#victim, " victims detected") --make sure that victims were found
            for i, v in pairs(victim) do
                coroutine.resume(coroutine.create(function()
		print("About to do if statement for", v) --make sure the coroutine is running as expected
                    if v.CameraMode == Enum.CameraMode.LockFirstPerson then
			print("About to switch to Classic mode for", v) --make sure the 'if' statement is working
                        v.CameraMode = Enum.CameraMode.Classic
		else --explain what happened if the 'if' statement is false
			print(v, "did not have FirstPerson camera. CameraMode:", v.CameraMode)
                    end
                end))
            end
        end
    end))
end

If a print statement gives unexpected output, or doesn't even get run, this will inform you of what's actually going on. ex, if print(plr, "chatted thirdperson") --prove that the if statement worked was the last thing you saw in the output before a print(plr, "chatted", message) message, this would tell you that findTargets is encountering an error.

Do be careful: while using print statements to debug your program, it is very easy to introduce new bugs (ex if you assume something's not nil when -in reality - it could be).

Also, don't forget to remove the coroutines, which serve no purpose in this function. If you need to prove it to yourself, try experiments with them. ex, put this script in a new place:

function test(i, doWait)
	print("Starting test", i)
	if doWait then wait(0.5) end
	print("Ending test", i)
end
print("Tests all at once")
for i = 1, 3 do
	coroutine.resume(coroutine.create(function() wait() test(i, false) end))
end
wait(0.1)
print("Tests that wait")
for i = 1, 3 do
	coroutine.resume(coroutine.create(function() wait() test(i, true) end))
end
--Output:
Tests all at once
Starting test 1
Ending test 1
Starting test 2
Ending test 2
Starting test 3
Ending test 3
Tests that wait
Starting test 1
Starting test 2
Starting test 3
Ending test 1
Ending test 2
Ending test 3

The first set of tests proves that if the coroutine doesn't wait, the coroutine will finish before letting the next one start (if you want better proof of this, put in a for loop that runs for a 100k iterations -- it'll lag your computer for a fraction of a second or so, and you'll note that the same output is displayed). The second set of tests show what happens when a coroutine does wait: it lets the next coroutine start/resume.

[EDIT] I discovered that error messages are hidden when you use coroutines and the error message occurs before/without a 'wait' command. You can display the error message by checking the return value of 'coroutine.resume', which will return true if there was no immediate error or else false, errorMsg.