Answering the general call for strategy.
Firstly, I don't think Wanda's stack is in Jetstone airspace. They're in a hex outside. How do I know? Because they're not already being peppered with arrows, nor have they been hit with air defenses. This means anyone attacking Wanda's group has to enter the hex, and Wanda can attack anything that enters her hex. And for what it's worth, casters have always been able to cast off-turn. They just can't cast anything that crosses hex boundaries, absent extraordinary effects like uncroaking volcanoes.
1. The biggest real threat to Wanda is the archers & dittomancer. A quadrupled volley of arrows can bring down her stack, if it's shooting in the right place. But she's got Archons with foolmancy, plus Jack. I'm just sure Jack has enough juice left to make Wanda look like Sylvia, and vice versa--remember, people see what they want to see. Just putting that stupid hair-helmet on Sylvia would almost be enough. But the pliers can be made to look like a sword, and Sylvia's sword made to look like pliers. Put 'em in separate stacks. That gives Ditto a target, and that's going to be enough for Wanda to do something sneaky.
2. Ansom's toast. Name Sylvia chief warlord, her bonus in-hex may be enough to let her stack survive the barrage. Plus, chief warlord bonus will help disguise the fact there's no artifact bonus in the stack. She and Oss can fight the defenders while the real Wanda hangs out in reserve. That won't even seem out of place, and that stack will be a powerful fighting force. They'll mow through archers, possibly even outmatch a leadership stack.
3. Veil some archons on the ground. Disguise them as shrubbery, put 'em somewhere they'll be able to surprise attack high-value targets (chief warlords, casters). That won't cost any of Jack's juice, and it has the potential to be a real battle-turner. If an Archon can one-hit k.o. a dwagon, you know they can one-hit a caster. Best chance is if they can zap Ditto the moment he steps through the hex boundary.
4. After some high-profile units fall, decrypt 'em and throw 'em back in the mix. Even if it's just dwagons, decrypted dwagons are still going to be powerful units with full hits.
Wanda's force was designed to take the tower by air. It's a powerful force. Not enough to survive if everything in the battlespace hits it at once, but with good tactics and additional decryption, maybe powerful enough to force Tram to withdraw.