First, the "anchor_grapple" skill listed in drowned_anchor_A B C should be set to .ignore_guard true.

Second, in shared\trait\theDivinity.trait_library.json, find the following line:

{ "id": "block_effect", "data":{ "effect": "BarkStressHeal" }, "chance": 0},

Here chance should always be set to 1, not 0.

After these two steps, the fix is done. Although she might still crash if virtues while captured by the Drowned, everything will be fine after reloading, no more permanent soft-lock. And after she is virtued, she will be immune to capture just like other virtued heroes.