Open Send on Next Available Slot issue

I've been working with both the original code and with my customized send assignments, but in all cases I'm getting an error at line 70. Am I missing something here? TY:

const { sendPath } = event.props;
if (!sendPath) throw `Send Path is required`;

/**
* @param {object} args
* @param {(arg0: { getValue: (name: string) => boolean; setValue: (name: string, value: boolean) => void; }) => void} args.callback
* @param {boolean} args.doRestore
*/
function withEditViewConfig({ callback, doRestore }) {
    let config = sf.ui.proTools.getMenuItem('View', 'Edit Window Views').children.first.children.filter(c => c.title.value !== 'All' && c.title.value !== 'Minimal').
        map(c => ({
            title: c.title.value,
            isChecked: c.isMenuChecked,
            original: c.isMenuChecked,
            element: c,
        }));

    let funcs = {
        getValue: (/** @type {string} */ name) => {
            let item = config.find(c => c.title === name);
            return item ? item.isChecked : undefined;
        },
        setValue: (/** @type {string} */ name, /** @type {boolean} */ value) => {
            let item = config.find(c => c.title === name);
            if (!item) throw `Couldn't find item "${name}"`;
            if (value !== item.element.isMenuChecked) {
                item.element.elementClick();
            }
            item.isChecked = item.element.invalidate().isMenuChecked;
        }
    };

    try {
        callback(funcs);
    } finally {
        if (doRestore) {
            for (let item of config) {
                if (item.isChecked !== item.original) {
                    item.element.elementClick();
                }
            }
        }
    }
}

/**
* @param {(slotIndex: number) => void} callback
*/
function withNextAvailableSendSlotIndex(callback) {
    withEditViewConfig({
        callback: (view) => {
            for (let i = 0; i < 10; i++) {
                let btn = sf.ui.proTools.selectedTrack.sendButtons[i];
                if (!btn.exists) {
                    view.setValue(i < 5 ? 'Sends A-E' : 'Sends F-J', true);
                    btn.invalidate();
                }
                if (btn.exists && btn.value.invalidate().value === 'unassigned') {
                    callback(i);
                    break;
                }
            }
        },
        doRestore: false,
    });
}

withNextAvailableSendSlotIndex(slotIndex => {
    sf.ui.proTools.selectedTrack.sendButtons[slotIndex].popupMenuSelect({
        menuPath: sendPath,
    });
});