Nope, bupe doesn't show up as an opiate on a screening, neither does oxy/hydrocodone. That's basically because they're not opiates, they're opioids, meaning they are (in general) synthetically derived, using complex chemical processes, from the thebaine component of the opium poppy. As opposed to being codeine or morphine (or very simple derivatives thereof), which are technically the only drugs that are opiates.
Lots of good info above on this topic. It basically costs a LOT more for companies to test for opioids vs. opiates, so they typically don't do it.
And for the record, I think drug testing in general is f***ing fascist bull***t. The only reason I think they're justified is if you're like an air traffic controller, or drive/pilot a commercial vehicle, like a bus, a plane, or a big rig. But a drug test to work at Home Depot or Walmart?!? F*** that, man. They can stick their crappy job up their you-know-what's as far as I'm concerned.