There is a mechanism to have a player released from a storyline. If you just allowed free agents to leave the league, that should simulate defections, as well as give you a storyline behind it.
But what little documentation there is on the storyline.xml file, I couldn't even make the event fire. I assume it would look something like:
Code:
<STORYLINE id="Cuban Defection" random_frequency="9000" min_usage_interval_days="60" player_nationality_id="49">
<REQUIRED_DATA>
<DATA_OBJECT type="PLAYER"/>
</REQUIRED_DATA>
<ARTICLES>
<ARTICLE id="950" player_released="1">
<SUBJECT>[%personname#1 l] DEFECTION</SUBJECT>
<TEXT>[%personname#1 l] Has decided to defect.</TEXT>
</ARTICLE>
</ARTICLES>
</STORYLINE>
The nice thing about this, is if it could work, there could also be modifiers attached, like needing a certain work ethic or greed.