The BMS is built for that battery, so everything (in a quick glance) that comes up for it's p/n on the edge of the board just says it's for that battery. (google itself finds zero results for the full term, and only shows results for the battery p/n that is a subset of the characters of the BMS p/n). I didn't read them beyond summaries, so there could be other info
The only way to tell if it's "legit" is to test it's functions, by making sure it disconnects the cells from the outside world in normal usage upon LVC (during discharge turns off when battery is empty), upon HVC (during charge when battery is full), and upon things like overheating and overcurrent situations (which you may have to create artificially).
The basic parts necessary to do the functions appear to exist on the board, but whether they actually do them (are designed to under the conditions you want to use them under, and actually function under those conditions) must be tested.
Note also that conditions that can damage the BMS like overcurrent, or seriesing them so that higher voltages than designed are placed on the FETs when they turn off, usually damage the FETs in a way that leaves them *always on*, so that the BMS can no longer protect against anything. It's a silent failure, in that outside the battery there's no signal to you this has happened, unless you do test for HVC, LVC, overcurrent, etc. to be sure the battery does indeed shut off under those conditions. (that kind of test for this failure isn't a one-time thing, it'd be a regular test if you need to be certain it is working).