Goblin Lackey

|Creature -- Goblin| 1/1. Whenever Goblin Lackey deals damage to a player, you may put a Goblin card from your hand into play. US-U [Legal in Vin Leg.]
So, Lackeys deal combat damage. The stack is:
Goblin Lackey's triggered ability #2
Goblin Lackey's triggered ability #1
Resolve Goblin Lackey triggered ability #2, Goblin Matron comes into play and the triggered ability goes on the stack:
Goblin Matron's triggered ability
Goblin Lackey's triggered ability #1
Goblin Matron's triggered ability resolves, and then the next Lackey triggered ability resolves.
So, unless I missed something major, that works.