Default Shipping Bin Calculated Wrong

On 10.2.400.14…When adding lines to a packing list, the default bin after entering in order/line/rel is not a bin with quantity on hand for some lines. Over 99% of lines added always default to a good bin with QOH. Can’t figure out why a couple of these outliers though are coming up with a wrong bin. Coincidentally, it is always the same wrong bin when it is wrong. I have tried setting that bin to inactive, but it will still default for those parts.

Setups:
Site config -> Default in the Order Shipping Warehouse/bin = false
No primary bins are defined under the parts in question.
Not using fulfillment workbench.
No bpms or customizations

Epicor has reviewed, and has requested the db. Has anyone else experience this, or know the logic of how bins are calculated during method GetOrderRelInfo while I wait on Epicor?