hi
The fire protection will be lost as it works only in a confined area, when the cowlings are closed and is anyway only working for fire outside of the engine.
There is a fire detection (loop) on both sides...
The EEC is in a protected blanket, no water ingression possible
EEC is normally cooled by a air scoop in the air intake, so in that case it was very well cooled.
If the pilot does not see (how could he) there is no way to know a cowling is lost except of the nacelle temperature indication if the aircraft is equipped..
And again there is a procedure in the AMM for all work requesting engine cowling opening.
Engine cowling opened for xxxx reason
Engine cowling closed Sign by X
duplicate inspection performed Sign by Y
Now in our engineering world we have the same as crew, we call it procedures.... of course if you do not follow....
Funny I did open a 330 cowling 2 hours ago... and closed it after all that handwriting.