Instead of posting that useless comment, you could actually have posted the data I asked. What you don't realize, is that I am in direct discussion with a Google Voice employee about this issue, and I've posted exactly what we've examined and learned so far. It is SOP to collect data to troubleshoot problems. Without actual failure data, which is identified as being on a specific Google account, that the engineers at Google can look at, there is nothing useful to identify the failures.
There are specific US FCC regulations regarding the privacy of Customer Protected Network Information, and neither I nor Google can simply troll through millions of customer's records to magically find the problem.