No. On the face of it sounds like a problem of Rumblefish stealing from users.
It's not accurate when the RIAA says stealing like that, and it's not accurate when anyone else does either.
The ads on the video pay out to Rumblefish instead of the video's owner.
The word "steal" still obscures the true nature of the problem, which is one of demanding services they have no right to based on a flawed law. That's not theft, though it could be described as fraud, extortion, or racketeering.
If you really want to be pedantic, "steal" is not a legal term. It's a term of common English routinely used to refer to any of theft, fraud, extortion and racketeering.
I find it hard to equate an automated (bad) copyright takedown with any of those terms. Or file downloading, for that matter.
Exploiting an automated takedown system for the purpose of extracting advertising revenue from non-infringing content to which you don't own the copyright is undeniably fraud.
Fraud requires intentional bad faith. You can't accidentally commit fraud. (And there is no proof that this was anything but human error.. you could probably make a good case for gross negligence though.)
You can't know intent in either direction. That's an issue of determining guilt, but this thread is a (ridiculous) digression on whether it's linguistically appropriate to use the word "steal" in reference to the takedown request. I assume you would therefore agree that it's valid to say that Rumblefish has allegedly stolen the ad revenue. So therefore you agree, right?
Only that this wasn't a DMCA request. It was a request from Rumblefish to Google, using a Google channel. I'm not trying to defend DMCA, but it wasn't used here.