Feel terrible! Getting upset just thinking about walking into one of my rooms and finding one of my fish on the floor..... Had a rope fish slither his way out once but only had him a couple days.....
I had a Violet goby do that once, I didn't find him rite away because he was on the other side of the room...
But i have sence learned that some of these fish especially the endis and prehistoric fish can "reconstitute" themselves and If you was them off and put them back into the tank they will rehydrate and be fine. I have never seen it for myself though.