In case someone else has this problem. Here is what Strymon said.

The issue here actually is due to the way EHX deals with something called reset timing.

When the Zuma is first connected, it ramps up power as a self-protection scheme. Digital pedals that are then connected see the low power at first and do not power on. A reset timer tells the internal processor to re-try powering on after a period of time. If this is too short, or not done at all, the pedal will never realize that the current has ramped up and is adequate to power on the pedal.

We have found that running the pedals off a current doubler (NOT voltage) will provide enough immediate current to power the Mel9 (so, it should work for the others as well). However, this does mean you would need 6 outputs for all three. The other thing we have tested successfully is, you can take one current doubler across two outputs, and then daisy chain the pedals off the current doubler. This does work, but could introduce some noise depending on the pedals. But, it does keep the amount of outputs used down to two, which is a gain from having to power all three individually.