Damn, we are burning through money to rescue Pisca and Saenar. Two 700 gold scrolls so far, and I'm about to vote to use a 2,275 gold Greater Teleport scroll. I hope the princess is willing to reimburse us for our efforts? We might be rich, but we aren't a charity.
Here's what I've got so far. Basically, it's the same scheme we were planning to use to transport the Iruxi with us back to Andoran. The Reduce Person scrolls won't last long, though, so even if we have six of copies I don't want to try using all of them. Six seconds per scroll, call it 30 seconds to cast the spell and get all four of the extra guards in the bag, Teleport, then 10 or 12 seconds to get them all out. That's cutting it close, but the bag has a large internal volume and can hold up to 500 pounds, so even just getting a couple of them out immediately should be enough if there is something to delay the rest from exiting it.
EDIT: Based on the limits of our buff spells, we shouldn't try to bring more than three of the princess's guards along, so I've updated the plan accordingly. We might not need to use Reduce Person on them, since a 500 pound weight limit is pretty good when you consider Cob weighs less than 40 pounds, IIRC, and Sirim is weightless.
I've got multiple layered Invisibility spells used here; individual spells on group members, plus an Invisibility Sphere to hide everyone. The sphere isn't really going to be good for long, since anyone who leaves the radius or attacks will become visible, but we only need it long enough to obscure our arrival and confuse any onlookers while everyone gets sorted out.
I've got everyone in our party covered by Invisibility except for Gorok, who will be using Mirror Image and Shield spells for added defense.
[X] The princess rushes to rescue the knight!
-[X] Gorok's Ghosts will accompany the princess and her guards on the rescue mission. We have a Greater Teleport scroll we can use to instantly transport a small group to Sir Pisca's location.
--[X] If she agrees, we will teleport the party, the princess, and three of her guards.
---[X] Prior to teleporting:
----[X] Ask the princess to use whatever long-lasting buff spells or effects she has available from scrolls or other items which could aid the rescue attempt. If she can provide Communal Darkvision, Communal Delay Poison, or Ashen Path effects, that will allow our party to preserve our limited powers for later use in the fight.
----[X] Ask the governor if he can quickly source a functional greatsword, perhaps from a member of his guard, and a chain shirt as well. If we are able to rescue him, it would helpful if he isn't defenseless for what follows. Alternatively, if the princess has a scroll or wand of Mage Armor, that could work as well.
----[X] Kori will cast Bless on everyone and Invisibility on himself, then activate his Cloak of Darkness. He will the use Inspired Spell to cast Extended Ashen Path (20 minutes duration each) and Communal Delayed Poison (1 hour duration each) on everyone, and activate his Unfettered Shirt immediately before Mina teleports them.
----[X] Mina will cast Mage Armor on herself, if she hasn't already, along with Hermean Potential and the See Invisibility spell she stored in her ring earlier. She'll cast Encouraging Mythic Heroism on Gorok after using her 3rd level Pearl of Power to recover the spell. She then casts Invisibility on Cob and herself.
----[X] Sirim will cast Mage Armor on himself, if he hasn't already, along with Magic Circle Against Evil, Mirror Image, Invisibility, and Shield. He will use Wild Arcana to cast Communal Darkvision on Gorok, the princess, and her guards.
----[X] Cob activates his Unfettered Shirt immediately before Mina teleports them.
----[X] Gorok will use his Scabbard of Keen Edges on his sword, allow Cob to use it on his dagger, and offer the princess or one of her guards its final daily charge. He will then cast Lead Blades on his sword, and Mirror Image and Shield from his ring, then activates his Unfettered Shirt immediately before Mina teleports them.
--[X] Gorok, Kori, Mina, the princess, and a guard of her choosing will be the main passengers of the our Greater Teleport scroll, with the destination being the chamber where Sir Pisca is being held. Cob, Sirim, and two of her guards will travel inside of our Type II Bag of Holding.
---[X] Mina will use a Reduce Person scroll if necessary to make room for two of the princess's guards along with Cob and Sirim in our Type II Bag of Holding. As soon as everyone is in the bag, Mina will use her Fortune Hex on herself to help her use the Greater Teleport scroll. She will use the rerolls from her Hex and from her Hermean Potential spell to succeed on the caster level check, if necessary.
----[X] Upon arrival, Kori will open the Bag of Holding to allow first Sirim, then Cob, then the princess's guards to exit.