Foreign Donations Missing Anonymous Part

For all the complaints about foreign donations going to the Chamber of Commerce which is funding political ads, I'm surprised more isn't made of the anonymous part. Anonymous donations were actually brought up in the Citizens United decision and 8 out of 9 justices thought it was constitutional to require donators be named (that is banning anonymous donations). Thomas was the only one supporting anonymous donations (on a free speech grounds, since it would clearly stifle those speakers that wanted to remain anonymous or felt threatened). Now it's a bit different since it's not donations directly to candidates but to groups that directly produce "political ads", but I'm still surprised I haven't heard mention of it at all.