Not being a patent wiz, I can't speak for the breadth of Dr.Wongs' patent or if it also covers Cd-free. That became more of an issue after this patent was granted as I recall.
Also as I recall, the tetrapod patent doesn't limit the production of tetrapods to QMC or anybody else, the patent is for the 'process' by which they are manufactured.
As a sidenote; (which may or may not involve the patent reference you quoted), Dr.Wong had to fight for this patent to be granted...it was at-first rejected by the USPTO examiner, but Dr.W was able to prove that a previously granted patent that appeared to be 'prior art', did not perform as claimed by the grantee. Wong eventually won-out on appeal & was granted the patent...which I suppose, nullified the discredited prior art claim in the process. I don't recall the names or patent# attached to the discredited patent, I just remember monitoring it as it happened (& posting it here) a few years ago...the data was buried deep in the USPTO patent app files.