Remove Track from 1 group

Try this. You'll just have to ensure every group you have is visible in group list. I haven't found a work around for that yet:

function getGroupRows() {
    let editWindowMenuItem = sf.ui.proTools.getMenuItem('Window', 'Edit');
    let mixWindowMenuItem = sf.ui.proTools.getMenuItem('Window', 'Mix');

    if (editWindowMenuItem.isMenuChecked) {
        let groupRows = sf.ui.proTools.mainWindow.invalidate().groupListView.childrenByRole('AXRow');

        return groupRows;
    } else if (mixWindowMenuItem.isMenuChecked) {
        let groupRows = sf.ui.proTools.mixWindow.invalidate().tables.whoseTitle.is("Group List").first.childrenByRole('AXRow');

        return groupRows;
    }
}

function matchGroupsToSelection(groupRows) {
    sf.ui.proTools.groupsEnsureGroupListIsVisible();

    let groupsContainingSelectedTrack;

    const targetGroupRow = groupRows.map(r => ({
        groupName: r.childrenByRole('AXCell').allItems[1].buttons.first.title.value.split(/-\s/)[1],
        btn: r.childrenByRole('AXCell').first.buttons.first.value.invalidate().value,
    })).filter(g => g.btn == 'Track selection partially contains group');

    if (targetGroupRow) {
        groupsContainingSelectedTrack = targetGroupRow.map(row => row.groupName);
    }

    return groupsContainingSelectedTrack
}

function selectTracksInGroup(groupName, groupRows) {
    sf.ui.proTools.groupsEnsureGroupListIsVisible();

    const targetGroupRow = groupRows.map(r => ({
        groupName: r.childrenByRole('AXCell').allItems[1].buttons.first.title.value.split(/-\s/)[1],
        btn: r.childrenByRole('AXCell').allItems[1].buttons.first,
    })).filter(g => g.groupName === groupName)[0]

    targetGroupRow.btn.popupMenuSelect({
        isRightClick: true,
        menuPath: ['Select Tracks In Group'],
    }, `Group Not Visible`);
}

function modifyTracksInGroup(groupName, groupRows) {
    sf.ui.proTools.groupsEnsureGroupListIsVisible();

    const targetGroupRow = groupRows.map(r => ({
        groupName: r.childrenByRole('AXCell').allItems[1].buttons.first.title.value.split(/-\s/)[1],
        btn: r.childrenByRole('AXCell').allItems[1].buttons.first,
    })).filter(g => g.groupName === groupName)[0]

    targetGroupRow.btn.popupMenuSelect({
        isRightClick: true,
        menuPath: ['Modify...'],
    }, `Group Not Visible`);

    const modifyGroupWin = sf.ui.proTools.windows.whoseTitle.is("Modify Groups").first;

    modifyGroupWin.elementWaitFor();

    modifyGroupWin.buttons.whoseTitle.is("Replace").first.elementClick();

    modifyGroupWin.buttons.whoseTitle.is("OK").first.elementClick();

    modifyGroupWin.elementWaitFor({ waitType: "Disappear" });
}

function main() {
    sf.ui.proTools.appActivateMainWindow();
    sf.ui.proTools.mainWindow.invalidate();

    let groupRows = getGroupRows();

    let nameOfTrackToRemove = sf.ui.proTools.invalidate().selectedTrackNames[0];

    let groupsContainingTrackToRemove = matchGroupsToSelection(groupRows).filter(gn => { return gn !== '<ALL>' });

    let removalGroup = sf.interaction.selectFromList({
        title: 'Remove Track from Group',
        prompt: `Please select which Group you'd like to remove the Track from`,
        items: groupsContainingTrackToRemove,
        oKButton: 'Confirm Group',
        cancelButton: 'Cancel'
    }).list[0];

    selectTracksInGroup(removalGroup, groupRows);

    let selectedTracksInGroup = sf.ui.proTools.invalidate().selectedTrackNames;

    sf.ui.proTools.trackSelectByName({
        names: selectedTracksInGroup.filter(tn => { return tn !== nameOfTrackToRemove }),
        deselectOthers: true,
    });

    modifyTracksInGroup(removalGroup, groupRows);

    alert(`${nameOfTrackToRemove} removed from ${removalGroup}`)
}

main();