No, too easy if it ties together.
the wizzies were out in the astral, great.
"Our Hero" was guarding them, great.
The Ancients bust down the door, great.
The Ancients attack because the astral quest was for spirits to be used against them, not so great.
Too much reason to hate the ancients, too narrowly focused character.
He'll just be another looser with a grudge against the Ancients.
Maybe the Ancients were hired by whomever the spirirts were to be sent against, but in that case, he shouldn't know that. Suspect it at the out most. Or the 2 pieces could be entirely unrelated, when did the Ancients last need a reason for attacking an ork?