DM guidance - Ravenscraeg Hall -Near TPK *spoiler

[Eretas]

Hi,
My group decided to reach Ravenscraeg Hall (tome 2) by climbing the walls and entering by the roof. One of them was attack by a raven swarm and leave the area to let the other one climbed. But he is a druid under gecko form and turn in human form and is now unable to climb again.

The group reach the aerie, they begin to fight the Ravens swarms. As they fight, one of them decided to enter by the roof trap. The 3 tengu knock him down easily. An another one try to surprised them and jump from the roof and fell.

Group minus 3... The 2 surviors get down the roof to enter the Tengu Rookery after using glitter dust to remove the vanishing option of the ninja.

Now, as the ninja fight them, Wodes, move in with another swarm and i don't see how they can survived,
2 against 2 tengus, 1 raven swarm and Wodes, the Blood-Feather Raven...

So I'm in need of suggestion, the lone one, try to reach the top by himself inside, but he won't be able to reach them on time if ever.

[Uqbarian]

Will the lone druid even be able to save them if he gets up in time? Has he used up all of his wild shapes for the day?

If they've lost 3 PCs, the druid might be better off running away and bringing back the NPCs (and maybe other help from Kalsgard). The bad guys are likely to keep captured PCs alive for questioning for a while.