Nice to be able to explain so many things mexican here.
Of course, the ajolote and axolotl are the same animal. Actually ajolote is a spanish spelling of the nahuatl aztec term axolotl which is term used by the native speakers.
Phonetically ajolote and axolotl sound very similar. remember that the spanish conquistadors and the franciscan friars made spanish versions of many nahua words, another example is ocelotl which in spanish is ocelote and in english ocelot.
There are many interesting things in the history of the axolotl. It was discovered by western science due to Alexander von Humboldt who collected the first specimens in Lake Xochimilco in 1803, sent them back to Paris where Cuvier studied and bred them for the first time in captivity at the Menagerie des jardin des Plantes. From the axolotls Cuvier kept there, he developed important advance on ontogeny ( Stephen jay Gould has a nice essay on all this). Currently, the largest pure bred group of the lake Xochimilco axolotl are at the Zoologico Los Coyotes and Chapultepec zoo, though the Universidad Nacional Autonoma de mexico also has a large breeding group.
There was a plan to have a mega development at lake Xochimilco, which at one even included a kind of Sea World. Fortunately, lake Xochimilco has been declared a world heritage site by the United Nations because of its ecological importance to all the valley of mexico, and its continued agricultural use for more than five hundred years. The mega development that was halted would certainly have finished the last remaining native Lake Xochimilco axolotls. It is hard to call them wild axolotls. Yet, cleaning up lake xochimilco has remained very difficult, because of the pollution that still affects the lake, acid rain runoff and garbage, garbage of millions of people. But it is clear that when the native axolotls of lake xochimilco dissapear it will be a terrible omen for the enviromental balance of the city founded by the aztecs 500 years ago.
