Fuck, that's a tricky one. In Guitar Pro I punched in 9 triplet 1/8 notes (i.e. one more than the bar can take) and the bar length indicator says the bar is 4.333. How the fuck you can accommodate 0.333 of a beat into a time sig is beyond me! haha

Have I understood your question correctly? Is it a case of a 4/4 bar with one "extra" triplet 1/8 note, like this?

Maybe the author of the tab simply fucked it up. Do you have a link?