How fast are cells spawning? You can use browser logging to determine the UID of the picked Cell and see if it's the correct one and also log the parameters being sent through to locate the error.
edit : I see you used a text object for the params so you must know they are correct then check if the picked Cell is correct. You could use something better than last created which is to send the Cell's UID through as a parameter since you spawn it before and then pick Cell based on this UID within the function.
I don't quite understand you, I have no use for UIDs now - only a function. Other methods don't work, this one at least works 90% of the time. Cells spawn very quickly and independently of each other, and to be honest, I'm not sure how the function works and whether it can be executed multiple times at the same time.
https://drive.google.com/file/d/11_nax6RJXo0rXkwuOmfr8bz_ZWsajG3b/view?usp=sharing - here is project