Youtube/google placed the access control and is the only party with standing to sue over the violation.
No, I think you are mistaken, but only due to a funny nuance in DMCA. The copyright owners do have standing (even though they didn't apply the DRM) and Youtube (who did apply the DRM) arguably doesn't!
Behold the legendary 1201(a)(3), where there are a pair of extremely unintuitive definitions, emphasis mine:
(A) to "circumvent a technological measure" means to descramble a scrambled work, to decrypt an encrypted work, or otherwise to avoid, bypass, remove, deactivate, or impair a technological measure, without the authority of the copyright owner; and
(B) a technological measure "effectively controls access to a work" if the measure, in the ordinary course of its operation, requires the application of information, or a process or a treatment, with the authority of the copyright owner, to gain access to the work.
(I'm focusing on 1201(a)(3)(B), though 1201(a)(3)(A) has some interesting implications as well.)
I read this as saying it's the copyright owner who decides whether or not the application of DRM is authorized, not the party who actually applied the DRM. And if the DRM isn't authorized by the copyright holder, then there is no access-limiting technological measure to be circumvented. We never even get around to having to read the definition of circumvention, because there's no [authorized] access control in the first place.
So if you upload your video to youtube, and then youtube, without your authorization, slaps DRM on it, then people who break the DRM and access the video are not violating DMCA!
(They can also be freed of violating DMCA even if you do authorize the application of DRM (1201(a)(3)(B)), as long as you also authorize people to break that DRM (1201(a)(3)(A)), but that's beside the point -- yet also what my sig happens to be about.)
But if you do authorize youtube to slap DRM on it, then people who access the video without your authorization do violate DMCA, and you, not youtube, are the "injured" party when youtube's DRM is broken without your permission.
If you or anyone else reads 1201(a)(3)(B) differently, I would love to hear your views. AFAIK there's no case law on this particular aspect of DMCA, so far.