I found a workaround for the other accessibility issue that was preventing me from tabbing through the select checkboxes. I removed the following section of code from the async-table.js file.
n.handleKeyDown = function(e) {
var t = n.props,
r = t.setProps,
o = t.is_focused;
if (q.c.trace("handleKeyDown: ".concat(e.key)), a = e.keyCode, ![Y.CONTROL, Y.COMMAND_LEFT, Y.COMMAND_RIGHT, Y.COMMAND_FIREFOX].includes(a)) {
var a, i = Q(e);
i && e.keyCode === Y.V || e.keyCode === Y.C && i && !o || (e.keyCode !== Y.ESCAPE ? (!o && J(e.keyCode) && n.switchCell(e), o && !J(e.keyCode) || (e.keyCode !== Y.TAB && e.keyCode !== Y.ENTER ? e.keyCode !== Y.BACKSPACE && e.keyCode !== Y.DELETE || n.deleteCell(e) : n.switchCell(e))) : r({
is_focused: !1
}))
}