Charmed and Dangerous - S4-E13
Other mistake: In this episode, the Source talks about the "Ultimate Power" being the Hollow. But in Season 8, we learn that the "Ultimate Power" is Billy and Christy. (And they end up taking in the Hollow, so now are they the "Ultime Power" times 2?) Which is it? It can't be both. (00:02:05)
Plot hole: When Gith takes the potion from Chris, he ends up stomping on it and shattering the potion bottle - making contact with the potion. We've seen that potions don't have to be thrown by someone who's even a witch for them to work (like when Cole's powers were stripped etc) so why on earth would he do this? And how did it not vanquish him? There are other ways he could have gotten rid of the potion that didn't involve a way that really should have vanquished him.
Trivia: Holly Marie Combs's real life pregnancy with her son Finley Arthur Donoho was mirrored by Piper's pregnancy with Chris in this season.
Answer: That was a mistake in the series.
Also, the episode is called 'Babies First Demon' and this alone tells us that it's Wyatt's first time in the field (so to speak) and as the sisters say, they've done a good job of clearing up their own magical messes so far. Nobody really knows how advanced Wyatt's powers are, or will become. That's why the cleaners appear, to nip things in the bud. The Cleaners didn't want to chance that the sisters could clean Wyatt's magic up, just incase they couldn't. Therefore intervening themselves, just in case.