FINALLY got to fight him. Will try to replicate my usual error next time, but if you want to narrow down when it does work, here you go.
Lini met Jordimandus in the Desecrated Vault, had nothing to sacrifice to get him to stay. (Usually, I do,, it doesn't prompt me, and after fighting his summon he disappears. Looks roughly the same.) Verified he was still there via an eagle. Amiri moved Lini away at the end of Amiri's turn so the next combatant would have him to themselves. Rest of party has uneventful turns.
Seoni at bat. Moved to Vault from Throne Room, explores. I close about half the available rooms. Of note, Marisiel closes her room by opting to bury her hand, then cancelling, resulting in a closure with a full hand. It's a tough dungeon, I don't mind using the occasional exploit.
Sheoni fights a summoned troll, uses Acid Blast, fails. Troll deals 5 damage. Unmitigated, this cleans her out, leaving nothing in her hand.
Here's the weird part. For the first time ever, the game allowed somebody, a cleaned out handless Seoni, to fight him. He didn't vanish. She lost, so he did what undefeated bosses do, but at least she got to try. If I can replicate this success, I might be able to beat this dungeon.
What device type are you on? Android
What version of the OS are you running? Android 4.4.2
What model is the device? Kyocera Hydro Vibe
What is your PFID#? B2BB9EA644E3908B
Is pass & play on? Is permadeath on? No, and no.
Tutorial, Story Mode, or Quest Mode? (If not quest mode, did you recently enter it?) Story. I had relatively recently reentered, when I used Seoni, having encountered Jorgi via Lini, had my usual luck, and verified by eagle he was still there to fight on the next explore.
Characters in Party: Ezren, Kyra, Amiri, Seoni, Lini, Marisiel
Location of each character: Ezren, Thassilonian Dungeon. Kyra, Shimmering Veils of Pride. Amiri, Festering Maze of Sloth. Seoni, Desecrated Vault. Lini, Festering Maze of Sloth. Marisiel, Abjurant Halls of Envy.
Turn Order as above.
Scenario & Scenario Difficulty. Normal.
What card was encountered when the issue occurred? (Or check, or card just played, etc) Jorgimandus, summoned a troll. Again, this time it worked right. First time without an error ever.
Did the issue occur on the first explore or a subsequent explore? If subsequent, what card did you last encounter? First, after moving at turn start.
What was its resolution? (IE, you just encountered an enchanter and failed the check, and on an additional explore you ran into a blessing of the gods but didn't auto acquire it)
Did other characters aid the check? What did they use to aid it? Failed vs. Troll, had no cards in hand. Jorgimund challenges Seoni, Seoni loses, Jorgimund escapes. No aid.
Was the encounter a Horde? Jorgimund plus a summon.