Alaundo is a link to everything in the FR and has nothing to do with Bhallspawn specifically.
Yes, Alaundo has a link to a lot of events in FR, being a great sage. He specifically predicted the Bhaalspawn crisis though:
The Lord of Murder shall perish, but in his doom he shall spawn a score of mortal progeny. Chaos will be sewn from their passage. So sayeth the wise Alaundo.
