Well, I got desperate (did I mention that I REALLY LOVE this workflow?) and ended up writing my own version in AppleScript. It only works with Chrome, because that's all I really need it for, but I may try to add other browsers sometime in the future.
A warning: this is my first foray in AppleScript and only my second workflow, so it probably is terrible and will crash and not work for you. You have been warned.
Known bug! If you have a Google Search open in a tab, it will not show up in the filter results. I'm not sure if this is because Google is using some proprietary Chrome API which makes Google search tabs somehow different than regular webpages? But for the time being I have not found a way around this. I'll try to fix it soon. Since I usually use tab search for hopping between email, Toggl, Trello, github, etc, it doesn't really bug me too much yet.
I was failing to clean/escape the url's being returned, hence the inability to scrape for tabs of Google Searches. I've fixed that and will upload a new version (which also works with Safari) momentarily.
Much of this is based on this very helpful post, "Generate Feedback in Alfred 2 Workflows": http://www.johneday.com/617/generate-feedback-in-alfred-2-workflows
Here's the workflow: http://static.etling.com/assets/SearchChromeTabs.alfredworkflow