It seems like your issue isn't the post, it's your company's attitude towards customer feedback. You're dead right. No company is 100% positive. That's exactly the point of reviews and why they are so valuable.
It's been well studied, and proven, that 5 out of 5 is not the best ranking. Something closer to 4.5 - 4.7 is. Why? Because no one believes in perfection. People will seek out the negative to understand how a business or service may not be a fit. Embrace that fact, understand it and use it.
Do what you need to around the symptom but do it right. That doesn't mean blackhatting your SEO rankings up or their page down. You'll get caught or banned from google or end up helping the article. There's no win in that method.
Instead start a social campaign to your customer base and start it today. Get 50 or 100 or 500 reviews published on your new community site [the one you're going to build this afternoon]. Turn Twitter from an idea into something you actually use. None of them are going to rank overnight but that's just reality -- you can't reverse a trend that took months or years to build in minutes just because the phone is ringing. With every request for feedback you risk more exposure but as you can see now, people are talking with or without you asking them to, your mistake has been not rallying them together to build to a critical mass in any one place... scattered blog posts are easily placed at an extreme.
Unfortunately it often takes it's incidents like this to get companies to act on building their reputation but so be it. Without a group of advocates, a community of followers or at least a review history you are on the wrong side of the scale. The only solution is to balance it.
There will be more bad that comes out down the road, justified or just the 1 in 100 who has something go wrong. That's the modern world. Stop being reactionary for a minute and think about how this moment will prepare you for all of those calls because they will come.
On a related note, be careful what you say out there: No matter how anonymous you may feel the internet has a way of creeping up and trying to mask a negative experience, or telling those who suggest you don't do so to get lost, has a great way of coming back to bite you.