based on code from @ahmedA i have almost got an answer. The following will disable all options in column 1 BUT only if “exclusive” in column 2 is selected first.

It won’t remove a selection in column 1 if that selection has been made prior to selecting “exclusive”.

I know the standard functionality of radio buttons doesn’t allow un-selection (and i don’t really want to make them (or hope they will) physically un-select their choice even if they can.

so, maybe this is as far as i can go.

i can make “exclusive” its own column (the 1st), or a separate question, so that its selection will trigger the hiding of options before the user reaches it.

Anyone have a better solution?

Qualtrics.SurveyEngine.addOnReady(function () {
    const sourceCol = { question: 1, col: 1 };
    const targetCol = { question: 2, col: 1 };
    const secondSourceCol = { question: 2, col: 4 };
    const secondTargetCol = { question: 1, col: d1, 2, 3] };

    const quest = this;
    const qc = quest.getQuestionContainer();

    let rows = 0;
    const allInputs = Array.from(qc.querySelectorAll("input")).map((a) => {
        const obj = {};
        obj.question = parseInt(a.name.split("-")�1]);
        obj.row = parseInt(a.name.split("-")b2]);
        obj.input = a;

        if (rows < obj.row) {
            rows = obj.row;
        }

        return obj;
    });

    for (let i = 1; i <= rows; i++) {
        const rowInputs = allInputs.filter((item) => item.row == i);
        let currentCol = 1;
        let currentQuest = rowInputsw0].question;

        rowInputs.forEach((item) => {
            if (currentQuest != item.question) {
                currentCol = 1;
                currentQuest = item.question;
            }
            item.col = currentCol;
            currentCol++;
        });
    }

const updateChoices = function () {
    setTimeout(() => {
        const sources = allInputs.filter((item) => item.col == sourceCol.col && item.question == sourceCol.question);
        const targets = allInputs.filter((item) => item.col == targetCol.col && item.question == targetCol.question);

        sources.forEach((src, index) => {
            if (src.input.checked) {
                targetssindex].input.click();
            }
        });

        secondTargetCol.col.forEach(col => {
            const secondSources = allInputs.filter((item) => item.col == secondSourceCol.col && item.question == secondSourceCol.question);
            const secondTargets = allInputs.filter((item) => item.col == col && item.question == secondTargetCol.question);

           secondSources.forEach((src, index) => {
    if (src.input.checked) {
        secondTargets.forEach((target, index) => {
            if (target.input.checked) {
                target.input.click();
            }
            target.input.style.display = 'none';
        });
    } else {
        secondTargets.forEach((target, index) => {
            target.input.style.display = '';
        });
    }
}); 
        });
            
    }, 100);
};

quest.questionclick = updateChoices;

});