Is the crack (in the first picture) just in the veneer or is it through the actual structure underneath? In the second and third pictures, it’s clear to see that chunks of veneer are missing. Unfortunately, this isn’t a quick fix.

Yes, it can be easily repaired. Get PC-Woody 2 part Epoxy Paste 1.5 Oz can, you can get it on amazon.com for a few dollars. It can be shaped to any profile and get matching stain to touch it up.

One of my customers a while back broke a drawer on a nice piece of furniture, a few professional furniture repair company's wanted $400-500 to fix it. She purchased PC woody and her husband made the repair under $10 including the stain. He even fixed a wooden drawer pull, 1 was missing a half of it. This stuff can be shaped to any form, can almost be used as play dough if you get the right consistency and sanded.

Good luck

I live in a very humid country. You think that's the problem?

Do you think one of these solutions would work?

https://www.wikihow.com/Fill-Cracks-in-Wood

There may not be a quick fix; but there is definitely a quick "disguise" with a Black Sharpie Marker--I use it all the time on my espresso and black wood for an instant, effective, scratch cover.

but if i just use a sharpie or marker won’t the split just continue getting worse ?

It looks like the wood has shrunk, perhaps from dry air? I had a coffee table develop a crack like this several months after purchase because of low humidity in our home. The company sent out a furniture repair specialist who filled the crack with a matching wax, buffed, and it looked good as new. The crack has not returned. I'm not a specialist, so I'm not sure whether such a repair will work for you. If you love the table, and want to keep it--I would definitely call the store you ordered it from, to see whether they can recommend someone you can pay (I'm guessing it is out of warranty?) to make the repair.

Yes, the sharpie will only disguise/diminish the lighter edges of a ding, dent, scratch or crack--it won't stop it from increasing, or fix it.

Not a pro. Wood filler and furniture marker would be my quick solution.