I dont understand why you use multiple keyers for garbaging and holding a matte. What you should do is
1) Make a decent key with the best edge result as possible and put the output to ALPHA
2- Using rotoshape, garbage and hold out what can be done easily.
3- Using dilate erode, shrink your matte a bit.
Now here is my method of keying
From you plate, plug a swithmatte node so that your plate is now into 2 nodes. The switchmatte and the primmate.
Under the primatte, MAX all your holdout stuff and MIN all your garbage stuff and pluus that part of the tree into the alpha part of the switchmatte
Now you can put a despill operation before the switchmatte
Here is a qucik exemple of what the tree could look like
http://hugoleveille.com/key.jpg