Discs burned fine according to the computer, BD player wouldn't recognize them.
One I burned with Nero, the other I burned with IMGBurn - both on WinData +R DLs. Third was an early attempt on a Memorex but I've since used those blanks up so I'm not concerned with trying them again. Used "Verify" on both of them.
TESB was burned on a Memorex and TPM is on a WinData and they both work, so I'm guessing the disc brands are not the cause.