Its interesting as I found a few example for mountains forming in craters on Mars, though the current thinking seems to be they formed through wind erosion, still it proves it can happen!
Example 1:
View attachment 239531
Example 2, the crater on the left:
View attachment 239532
Ok then. I may not know much, but I studied geology at university, so that's sort of a thing I kinda know (and like). I'll try to over simplify to make it short.
Mountains are usually formed at the boundary between 2 tectonic plates. Which are gigantic. Earth have around 15-20 of them (all of them added together from the entirety of our world).
Moutains form because 2 (or more) plates push against each other, over a long period of time. That's why mountains are "range". Like the Himalayas, the Alps and all the others. They follow a "line" if you will. Everything over that line, and at some distance away, is submitted to massive strength that'd make a nuclear bomb a wet fart.
If you have a crater there, it follow the same rule than anything else at the same place.
For example, India is pushing against the rest of Asia, going "north", the Himalayas mountain range is born.
What could happen is volcanism. Mars is more or less dead now, but it wasn't always true. Volcanoes are not mountains, they follow different rules. Essentially, magma poke through the land, and there you go, volcano. Sometimes magma inside the volcano cool down, but it's a much harder mineral than the surrounding. So, when the erosion star doing its thing, the "outside" is worn off much quicker than the inside. Eventually leading to a weird "mountain".
Once gain, complicated and simplified. Not really a rule per say.
There is also how the crater was formed, could be a result of that. Relatively similar to the whatever-you-call-it thing in the centre of them.
Eventually, as you see in the picture, those "mountain" are very small and barely above the crater itself. Which is different from the picture posted earlier.
Anyway, it was a lot of oversimplification, but that was the best I could do. Consider it nitpicking about calling those mountains
And in any case, it's fairly minor, as I said.