Invisible Bribed Units

[Live2sculpt]

I recently learned that it is possible for a unit to be bribed in a campaign, but because the unit is not listed as available to the bribing faction, it can appear on the battle map as invisible.

This has occurred in my campaign, with Italian Militia units in French Armies.

This MUST be a very common issue.

What should be done to correctly prevent this from happening?
What prevent's this from occurring in Vanilla campaigns?
Is there a topic that outlines this problem and its solution?

As this could fall under text editing (EDU) and skins issues, I'll ask in both topics.

[attyla]

You need to add bribed unit to modeldb for faction you are using.