I was going to brew a Octoberfest this week and pitch it on top of the yeast cake from a Munich Dunkel, well I got sick and could not brew and I needed to keg the Munich up yesterday, and am a little nervous about pitching into a dirty carboy so I kegged the munich and put the yeast cake into a sanitized growler and put it in the fridge yesterday, my question is, will it be ok in the fridge till Thursday and just pitch the whole cake or should I wash the yeast and make a starter and pitch that Thursday? Any thoughts on this?
I think you’ll be fine pitching it from the growler. I’m done all the scenarios you’ve mentioned above with no problems. I even let a yeast cake sit in a fermenter for a week before pouring the new wort into it!
It’ll be fine in the fridge for a week. Since you have time I would suggest you rinse the yeast to separate as much of the trub as possible. Either way, you don’t need to pitch the whole yeast cake - probably closer to half or even a quarter of it. If you want you can use the slurry tab on the MrMalty calculator to try to figure out exactly how much.
Ya thats what I was thinking, mrmalty rules!!!
Also, make a starter of any yeast you have saved. If it works, it works.
If it does not you will use one of the various varieties of dried yeast you keep on hand in your refrigerator. Right? 
Saving cakes is a good thing and fermenting on them is quick and easy, not to mention all the yeast you can save for the future.
Right now I’m reviving a 4 month old cake of 1007 I saved in a jar and kept in the fridge. Revived a 4 month old 3333 last week and it is now happily eating away my hefe 
Thats right.