The order of actions is quite tricky here.
We have a harpy singing, carrying over from last turn, which is both immediate and continuous.
For movement, we have Stern and Witherun compelled to move toward the harpies, but each being obstructed by Garamon and Goldwen, respectively.
Then we have Flin's missile fire, which (technically, btb) is resolved after movement but before melee.
Then we have two wrestling matches which (technically, btb) are resolved at the end of the turn in the melee segment. This is perhaps a tad awkward as, logically, these would occur more or less simultaneously with Flin's missile fire.
The ref notes that CM's simultaneous movement system has, for the MOVE segement: <<
Both sides move ..., making one-half of the move, checking for unordered melee contact due to opponent movement, conducting split-moves and missile fire and taking any pass-through fire; then the balance of movement is completed as ordered.>> with the MISSILE and MELEE segments coming after.
The "unordered melee contact" seems to best describe our wrestling matches, which would mostly realistically be initiatived
during the move segment, in much the same way pass-thru missile fire would be conducted during the move segment. However; life is not perfect. We simply have to imagine that everything is all happening at the same time, despite having to resolve things in a specified order.
Let's see how it goes...
--- end preamble; start resolving the turn ---
Harpies #1 and #2. MM says harpies are low intelligence, and U&WA says semi-intelligent monsters are distracted by food 50% of the time. Since the harpies were lured here by the scent of breakfast, the ref dices to see whether harpies #1 and #2 will go for the corpses or for the players. Odds=food, evens=players. 1d6=5, so feeding takes priority. Yhhhummy
Harpy #3 contains to sing her baleful song. And so...
MOVEMENT is divided into two halves, with pass-thru/split missile fire occurring between them, and unordered melee contact occurring at any point during.
Thus, Stern strides toward the portcullis winch and is intercepted by Garamon during the first half move (i.e., before Flin's missile fire, and thus before Harpy#3's song could be interrupted).
Witherun runs and jumps down the stair with all his hunter's grace, to be intercepted by Goldwen during the first half move.
The harpies make no meaningful move.
MISSILES
Flin draws back his axe, and aims his throw.... but firstly, will he resist the harpy song?
Flin saves as a champion so needs to throw 11+ and: 1d20=11! Exactly enough to save.
Flin (FC hero-1, THAC2 15) throws his magical axe +1 at the Harpy (AC 7) 1d20=9+1=10. That's... (ummm, math struggle)... exactly enough again.
Flin hits for 1d6=2+1=3 hp damage.
The harpy song is interrupted! But exactly when its compulsion effect ends is undefined... let's assume it will finish at the end of the turn.
MELEE
Stern (FC=4 men, strong=5 dice) will throw 5 dice.
Because this is all happening simultaneously with Flin's missile fire, Garamon (FC 4 men=4 dice) is still trying to block his ears. Thus he will be half as effective and initially throw only 2 dice. If this isn't enough to beat Stern's total, Garamon will instinctively and add his other 2 dice into the mix (bringing his to a total of 4 dice, but exposing him to the harpy song).
Stern 5d6 ⇒ 4,2,4,2,4=16.
vs Garamon's initial 2d6 ⇒ 3,6=9. That's not enough, so Garamon can't help but use his arms in the struggle, meaning he is exposed to the harpy song
In a similar process Goldwen (FC 3 men=3 dice) tussles with Witherun (FC 4 men=4 dice). Goldwen will throw 2 dice initially while protecting her ears, then add 1 more die when she frees her hands, if required.
Witherun 4d6 ⇒ 5,5,6,2=18.
vs Goldwen 2d6 ⇒ 5,2=7. That's not enough, so Goldwen too can't help but use her arms in the tussle, and is exposed to the harpy song
Garamon saves vs harpy song: He needs to throw a 14+ and: 1d20=7. That's not enough, so Garmon's struggle ends before he can apply his full strength.
Goldwen saves vs harpy song: She needs to throw a 12+ and: 1d20=20! She saves, so she can throw her full strength at Witherun.
Goldwen's final die 1d6 ⇒ 6! So her total is 7+6=13.
Witherun's total was 18, so alas Goldwen's efforts are not enough to stop her friend. But the struggle has at least delayed him (and Flin has interrupted the harpy song meanwhile).
Reaction Dice.
The harpies have each taken a missile hit. Their breakfast is proving to be far more prickly than they anticipated.
How will they react? 2d6=9.
Looks like they are keen to put up a fight for their morning feed...
What next?