Typo3 TSPage-Config: Accessing the flexform-xml fails

Question

i use the bootstrap_package in one project, but the problem is related to accessing felements within the xml in the flexform-databse-column of tt_content (Typo3 v11). Assuming i have a card_group element with items in it, i tried:

TCEFORM {
    tt_content {
        pi_flexform.bootstrap_package {
            sDEF.lDEF.align.disable = 1
            lDEF.align.disable = 1
            sDEF.align.disable = 1
            align.disable = 1
            sDEF.lDEF.columns.removeItems = 4,2,1
            lDEF.columns.removeItems = 4,2,1
            sDEF.columns.removeItems = 4,2,1
            columns.removeItems = 4,2,1
        }
        pi_flexform.tx_bootstrappackage {
            sDEF.lDEF.align.disable = 1
            lDEF.align.disable = 1
            sDEF.align.disable = 1
            align.disable = 1
            sDEF.lDEF.columns.removeItems = 4,2,1
            lDEF.columns.removeItems = 4,2,1
            sDEF.columns.removeItems = 4,2,1
            columns.removeItems = 4,2,1
        }
    }
}

My result should have been:

• Field card_groups -> options -> align should be hidden for editors
• Restrict card_groups -> options -> columns to "3" only (as an example)

Any hint / working example on card_groups and/or accessing pi_flexform-fields properly by tsConfig would be highly appreciated.

The XML of the pi_flexform-column of an existing element looks like:

<?xml version="1.0" encoding="utf-8" standalone="yes" ?>
<T3FlexForms>
    <data>
        <sheet index="sDEF">
            <language index="lDEF">
                <field index="align">
                    <value index="vDEF">center</value>
                </field>
                <field index="columns">
                    <value index="vDEF">3</value>
                </field>
            </language>
        </sheet>
    </data>
</T3FlexForms>

Any hint and/or help is highly appreciated.

Thank you, Th.