In a 125g, I'd get 3 more replacements. Maybe the other 2 could look out for the third.
Still, I'd consider that a blip on the screen and think chances are slim it'd happen again - unless you got that one killer goby. I'd bet still that the goby wouldn't go thru that again and have shrimp stuck in his mouth for a day or two.
Besides, only one shrimp in a 125g??? That's no fun
IMO. They seem to be out more in numbers rather than alone IME.