Your analogy is broken...
This is more like finding worms eating a corpse, and then saying it's proof that the worms must have been there when the person was living.
I can assure you that those samples were intact all these years. Besides, most of the samples were in vials and not in flasks. How do I know this personally? I did my PhD work in a lab right next to Jeffrey Bada's (see the paper, he's one of the main authors). I was there when he found these samples from their storage or something and told us all about it.
Also any amino acids that were in the vials must have been synthesized in the Miller's apparatus since there was no starting materials left in those vials (remember the S.M. were gases). Even so this experiment is still irrelevant to the origin of life for the reasons I've discussed in another comment of mine (see below).
Regardless, this experiment is still irrelevant because those gases Miller used (H2S, H2, NH3, CO2, esp.) cannot coexist in the same place for any appreciable amount of time. Gases like CO2 would not exist without a significant amt of O2, but H2S, H2, NH3, etc (and the amino acid products) would be quickly oxidized at elevated temp in the presence of O2. Moreover, if O2 was absent, unfiltered UV radiation (w/out O2, no O3 layer) would also quickly destroy those reducing gases and amino acid products.
365 Days of drinking Lo-Cal beer. = 1 Lite-year