The option you are using is for field not for the tree tag. so your xml will be like,
<field name= "types_id" colspan="8" nolabel="1" options='{"deletable": false, "addable":null}'>
<tree delete="false" string='YOUR STRING'>
<field name="type_id"/>
<field name="fundamentation"/>
<xpath expr="//tree/button[@string='Add']" position="replace">
<button name="button_cancel" string="Mark to Cancel" type="object" icon="gtk-cancel"/>
</xpath>
</tree>
</field>