Cluster Fig tree (Ficus Racemosa) Problem

I have a 5 year old cluster fig tree producing fruits.

I have a problem with the stem which looked like a sunscald, there was an opening through which ants transport some white material inside. I decided to cut around the opening and clean out the ant infestation, but once I cut it the outer skin started peeling off downwards.

Please see attached picture. The ant infestation problem is solved, but the opening on the bark still remains, exposing the inside.

Is there anything I should do to fix this or just leave it alone to get healed by itself?

It's fruiting but there is another big sunscald along the main stem on top.

That looks more like a fungal invasion than sun scald to me.
You might want to try brewing a good, aerated compost tea and saturating that area with the tea.

From there you have a few other options;
Cut off the affected area and use Elmer's white glue to create a temporary seal so no re-infection occurs while the tree heals over.
Doing this might be too drastic for you and your tree but it is the absolute sure fire fix.

You could wipe the exposed wood down with a 3% Clorox solution and then seal between the two sided of the bark with Elmer's white glue, so the bark can heal and reseal the tree.
This one isn't as certain to work as the cutting the infected area out, but it has worked on other fig species for me.

You can do nothing but observe to see what happens.

Good luck with what ever you choose to try, it's a shame that happened to the tree.