Take him to a vet!  You don’t want to mess with it and chance he loses his sight in that eye.  I also would try a wet wash cloth soaking it (use salt water — add salt to hot water until the water tastes like the ocean, don’t use water hot enough to scald you or the dog!) to help clean and flush the eye until you can get him to that vet.

I agree with Laura, lots of owners of small dogs think it is okay to let them use pee pads in the house — and of course the dogs get out of the habit of using the pads and end up going where ever they please after a few years.  I figure they put up with this since small dog turds are small and easy to pick up.

BUT, YUCK!  

Unfortunately unless everyone agrees to comply with a new regiment it is unlikely you will have much success house training these pooches.   To house train a dog requires a crate and a strict schedule.  Managing four dogs at the same time is more than I would want to take on and I own 4 dogs, and foster 1 or 2 more most of the time!  But, I only allow 1 or 2 unhouse-trained dogs at a time. Really that is the limit of what I can pay attention to!

You could try reducing the amount of pee in the house with belly bands and sugar britches (diapers for dogs – find them at CairnRescue.com or google for them).  They hold a sanitary napkin inside that keeps the pee contained — but since the dogs can go in and out the doggie door this will not teach them to pee outside.  It would just reduce the amount of pee in the house.

As for the poop – dogs often poop at a regular time.  Twenty mins or so after eating is normal, and some poop in the morning after a bit of walking.  If you force the dogs outside at these times (or when you notice a time they seem to poop most often) and lock/block the doggie dog you force them to poop outside, and after a while they may get the message and do their bowel movements outside.  

You also need to clean where they have been doing their business.  Use white vinegar mixed with water (50/50), add a drop of dish washing liquid (Dawn).  Put this mix in a squirt bottle and wash the walls, baseboard and floor.   Use this mix every time them soil in the house, especially around your doorway.  At the very least they will not like the smell and may move their marking farther down the hall!

This mix works as well as an expensive enzyme cleaner so don’t waste your money on that.  WalMart often carries “washing vinegar” or cleaning vinegar, it is a little more acid and costs the same as regular white vinegar.  Buy it by the gallon and use it generously.

Good luck!