Mystery BGA-149 NAND Chip

We have seen a few of these BGA-149 NAND chips in Verbatim flash drives from China. At first, they look like eMMC chips but they are actually custom NAND chips. Toshiba’s marketing material says they’re BGA-153 and intended for “high end class applications”. These chips do not use a standard NAND pin-out, we figured out the pin-out and can recover the data from them.

Controller: PS2251-68-5
NAND: THGBMFG7C2LBAIL (ID: 98 de 94 93)
Package: 11.5mmx13mm