I wouldn't mind if the "friends" were like the 2 cuties on the table!
I don't think oxalis are particularly prone to insect infestations. You might find a few tiny spiders lurking in there hoping for a meal.
If were me, I'd simply wrap a few plastic bags round the pot to cover the soil - and not flood the pot - and just wash the foliage gently under the shower or a soft spray from the hose. That should dislodge most things, then just shake to rid the worst of the water and let it dry naturally.
You can of course use an "organic" spray first and then wash off.
Your plant will go dormant anyway so no large pests will have any cover.

Here is a link that might be useful: garlic/onion/pepper spray

Neem oil should do it. Spray it down with that a couple times before bringing it inside.

Let it go completely dry and die back to the soil line. Let it rest, dry, for 1-3 months. Break apart the bulbous/tuberous root/soil mass & separate the root structures from the soil. Repot into a very fast draining soil and keep barely damp until the bulbs/tubers spring back to life. They will show their appreciation for the dry rest and for the thinning they need regularly. Plus, you'll have plants to share.

Al