Violation or no...would it be if?

[RefsNCoaches]

Team A scores, B1 grabs ball, heads OOB on baseline. Count starts, she sets ball on floor and runs onto floor. At the same time B2 runs OOB and picks up ball and throws inbounds pass prior to the 5 second count being reached.

Coach A is barking "that's illegal, she can't do that!".

At next stoppage in play Coach A asks me for explanation...I tell him I have a legal play just as if B1 were to make the pass OOB to B2 and then B2 throws it in because it was not a spot throw in. He said ok...

I don't think I kicked this one but was curious if it were a spot throw in if that would be legal and I want to say as long as the ball is OOB the entire time and the pass is released prior to the 5 count, we are ok ?

Thanks