You are free to interpret this comment as prohibition or as my blessing, but...

If it matters, ask your lawyer.

If it doesn't matter, it doesn't matter.

Or to put it another way, trademarks (you've mentioned two) and copyrights (it's a crapshoot) are complex. And in some jurisdictions (notably the US) anybody can sue anyone for anything.

Your risk aversion is yours, not someone else's. Your financial and legal wherewithal is likewise yours.

IANAL, but it might be relevant to others trying to answer what jurisdiction you are in. (US, EU, CN, JP, elsewhere?)

Also, when you bought from PianoDisc, did you agree to abide by a certain jurisdiction's laws in your use of PianoDisc? And did you explicitly agree to not share any sort of decoder/encoder in any ToS?