You have competing ideas. Wear-leveling is technology that spreads around where data is written. It appears as if tossing around data into cells at random. This is done to prevent the same area of memory from being constantly written to. The cells of solid state memory, unlike a hard disk, can only sustain so many write functions before those cells crap out. By randomly spreading around where data is written you can get more miles overall from a collection of solid state memory cells, longer product life. So even if you wipe a SSD and re-write the data back to it, you get data that is still scrambled and spread around in memory.
Now, the SSD must keep track of where the wear-leveling scheme wrote data, what cells are in use and what cells are available for writing to in the future. For simplicity, think of it as a look-up table. That LUT is external to the solid state memory cells. To corrupt a SSD you need only corrupt the LUT. Likewise, to "crack" a secured SSD, you need only monitor the way the LUT is managed to determine how the memory cells are being managed. This is why SSD security is a point of interest to folks wanting to protect data. They have a new set of issues to deal with that did not exist with HDDs.