Mmm, not good at all.
No matter, just put it down to a learning curve - bet you won't do it again
Try doing what I suggested about cleaning it off and let the damaged areas dry out. Over time and with an increase in growth, the damaged areas may callous over, but it's doubtful in the small pots. The trees would need to be re-potted into large black plastics or styrene boxes.
To stop them rotting any further, when they've dried out thoroughly, you could paint them with Lime/Sulphur solution, but make sure they really have dried out - even scrape some of the mix away to expose more of the lower trunk. Another product you could use is wood hardener available from Bunnings or other good hardware stores. Be careful though, they really do need to be totally dry in the affected areas before using either.
Something else you could do to save them is to take them out of those pots, cut 'windows' in the bark around the trunk just above the damaged areas, treat the windows with hormone rooting gel or powder and plant them deeper in black plastics above the windows. Effectively, what this is, is a ground layer and is not as invasive as an aerial layer.
I'm just about to do a post where I've stuffed up a bit on a fig, so you're not alone Dolicus