transmission looseing power due to alternator going bad?

What is your question?

i was driving my x5 when i saw, a small red battery flashing on and off every 5min and so. then a day after my transmission lost power,i heard a noise and then the transmission,lost power.i took it to bramen bmw, were i was took that my alternator was going bad and my wheel speed sensor. that this could make my transmission loose it power.,it was to much money,that bramen bmw wanted to charger me to fix the alternator,B.M.W.also said that i had to get the alternator and the senser fix, before they can see if the trnsmission has a diffrent problem.so i went and picked up my x5,when i strated to drive my transmission was working ok, untill that light strated to flash, on and off. my question is can ti be possible that my trasmission is looseing power bcouse of my alternator also looseing power?