Advice on 3rd Party Claims by companies like CDBaby and INDMusic

In the last couple of years, I’ve had to fight a few times for the users of my music.  Various people have come to me stating that their video was claimed erroneously by a record company.
There are usually one of two reasons for this.  The first reason is that because my music is royalty free, some people have taken it upon themselves to record lyrics over my original track and tried to put it on a third party YouTube Content I.D. database.  The other case is where an artist has used a similar plugin to me, utilizing only one setting (In my case, an EASTWEST Gold Orchestra setting that has a string section horror stab) and putting it on a Content I.D. database).
In both cases, I’ve found the best way to deal with these claims by going directly to the company issuing the claim.
In the case of the artist lyrics over my track it’s necessary to issue a takedown notice regarding the track, citing their artist and their track that they used my track with, and also the name of your track that the artist infringed upon, plus some sort of proof that it was your track to begin with.  In my case, having posted all my royalty free music on YouTube as representative of what I distribute on my website, I’m fortunate enough that the video gives me a time-stamp that proves that I’m the original source of the underlying track.
For the case where a sample from a VST plugin has been claimed, I always refer the company to the End User License Agreement to the product and use this as a basis to tell them that they cannot legally claim the track in their database.  I feel this one is a little more important to you guys who’ve tried to use the Apple Garage Band tracks in your videos and subsequently have them claimed to oblivion — the End User License agreement for that program should provide you with the legal means to combat your claims by citing them against the company that claimed you.
In fact, if you have used a piece from a company like AudioMicro, I would argue to you that it is up to them to defend your right to use the music, since you’ve either paid into the system or gained it through your contribution to your YouTube network, which has paid for access to those tracks.  If these companies offer their music as Royalty Free, then it is up to them to uphold the Royalty Free status of each track they offer.
So I would contact the company that provided you with the royalty free music and ask them to go to the company that claimed your music.  Include a link to the video that was claimed, the email you received stating that you got claimed, and any information on what the company it was that claimed your music, plus the artist and music track the company is claiming for.