I have edited wkf_holidays workflow in Holiday Leave Management Module. I needed to add a addtional valdation in between confirmed and validation and I edited out. I can see the node and new node in the existing workflow but the thing is validation button is missing and after the confirm it's not directing to my new node sub_confirm. Please help me out

workflow:

request leave--> confirm --> sub validate --> validate 1 --> validate2 --> approved

new node : sub_confirm

in workflow file I put call this new node block after the confirm

<record model="workflow.activity" id="act_sub_confirm"> <!-- submit2-->
        <field name="wkf_id" ref="wkf_holidays" />
        <field name="name">sub_confirm</field>
        <field name="kind">function</field>
        <field name="action">act_sub_confirm()</field>
        <field name="split_mode">OR</field>
    </record>

Transition

<record model="workflow.transition" id="holiday_confirm2validate"> <!-- 2. submitted->accepted (validate signal) if not double_validation-->
        <field name="act_from" ref="act_confirm" />
        <field name="act_to" ref="act_sub_confirm" />
        <field name="signal">validate</field>
        <field name="condition">not double_validation</field>
        <field name="group_id" ref="base.group_hr_user"/>
    </record>

    <!--new transition-->
    ***<record model="workflow.transition" id="holiday_sub2validate1"> <!-- 2. submitted -> first_accepted (validate signal) if double_validation-->
        <field name="act_from" ref="act_sub_confirm" />
        <field name="act_to" ref="act_validate1" />
        <field name="signal">validate</field>
        <field name="condition">double_validation</field>
        <field name="group_id" ref="base.group_hr_user"/>
    </record>***

    <record model="workflow.transition" id="holiday_confirm2validate1"> <!-- 2. submitted -> first_accepted (validate signal) if double_validation-->
        <field name="act_from" ref="act_confirm" />
        <field name="act_to" ref="act_validate1" />
        <field name="signal">validate</field>
        <field name="condition">double_validation</field>
        <field name="group_id" ref="base.group_hr_user"/>
    </record>

Button call in hr_holidays_view.xml file

<button string="Sub Confirm" name="sub_confirm" states="sub_confirm" type="workflow" groups="base.group_hr_user" class="oe_highlight"/>
<field name="state" widget="statusbar" statusbar_visible="sub_confirm,draft,confirm,validate" statusbar_colors='{"sub_confirm":"blue","confirm":"blue","validate1":"blue","refuse":"red"}'/>

Transition function in hr_holidays.py file

def act_sub_confirm(self, cr, uid, ids, context=None):

        res=self.write(cr, uid, ids, {'state':'sub_confirm'}, context=context)
        return res

Please help me to understand what I have done wrong.