I already replied in the support ticket that you submitted on the same subject. For convenience I will post my reply here as well.
First of all I would like to remind you that templates are rendered multiple times so using IDs inside is not recommended. Instead id="wordRowDelete"
please use class="wordRowDelete"
Regarding your question, in order to change the icon of a detailbuton you should remove current icon class and add new one which corresponds to the new icon. For example:
//change data attr
//remove old class
//add new class
For your convenience I prepared a small sample:
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