Are you using the H9 in stereo or mono? If mono, you can use the H9 in pre/post mode, where half of it occupies a loop in front off the amp and the other half occupies a loop in the amp's loop. That's really the only option aside form buying two.
Just be aware that the H9 does NOT handle a line level signal (most passive FX loops) and will clip badly at the H9's input. Ultimately, that's why I sold mine.