Is it permissible for my wife to go out with her paternal aunt and her paternal aunt's husband to take care of some needs?

If a woman goes out with her paternal aunt and her aunt's husband, while veiled and feeling secure from being in seclusion with her aunt's husband, there is no harm upon her. The forbidden seclusion is negated by the presence of a mahram for the woman with them, or by the presence of a trustworthy and capable woman.