5 panels and 3 tiers. Structured like a 6 grid.

Tier 1: panel 1.
Tier 2: panels 2+3.
Tier 3: panels 4+5.

4-12.1 Wide panel from behind Jane's head as she looks under the bridge. Barely visible in the murky water is a red object a foot or so under the surface, right near a fallen tree. The panel borders become wobbly.
JANE: ...Is that--?

4-12.2 Camera is in front of Jane as she creeps her way under the bridge and gently places her foot on a big chunk of concrete partially submerged in the water, still clutching the wallet in one hand.

4-12.3 Same angle as she cautiously ventures further onto the concrete block, her expression determined as she steadies herself to keep from falling in the water.

4-12.4 The concrete block and the fallen tree sit in the water, the river's current causing a patch of rough water around them.

4-12.5 Same image but now Jane's foot appears to cautiously step onto the tree, causing it to sink a little further into the river and disrupting the flow of water.