Heya
Session in Hextor temple: Two party members died in great battle against Theldrick and his allies. One managed to escape outside of mine. Two were left (one uncouncious) inside mine. Escaped one want to go garrison and report of danger (they already found both texts from Theldricks room). What you think that garrioson should do? They haven't been at Erythul's place at all and they have visited Vecna's place briefly. If garrison comes they can quite easily raid the place.
I'm worried about this as well (at least one of my party members has a tendency to think "out of the box").
Since your party is in such bad shape, I would actually let the escaped member go to the garrison. You probably won't be able to interest the supreme commander of the garrison, but Melinde (the Paladin) should be interested (especially with Theldrick's journals in hand).
Consider having Melinde gathering a "strike force" to investigate the mine, and let each player with a missing PC (dead or captured) take one of the strike force characters. It will get them involved, and provide a way for the "real" party to get the rest of the information needed.
The "real" absent PCs shouldn't get experience for the adventure (or maybe half XP if you are nice), so you may want to follow it up with a vignette or two to get the missing characters caught up.
Now, in my party's case, they aren't in bad shape, so I'm planning on having the garrison be more lazy (although I could add Melinde as a single NPC).
Thats a good idea having the players play members of the garrison to go in and clean up the trash sinc the PCs are in a pretty bad predicament.
In other cases, where I have had PCs take on the role of "law enforcement", I try to remind the players as a DM that their background is used primarily for hook and roleplay purposes and that THEY ARE the cavalry/heroes.