Has "induced savantism" been further explored beyond Snyder 2009? The Mechanism/Neurological subsection of the Wikipedia article Savant Syndrome says:


  Savant syndrome results from damage to the left anterior temporal lobe, an area of the brain key in processing sensory input, recognizing objects and forming visual memories.[citation needed] Savant syndrome has been artificially replicated using transcranial magnetic stimulation to temporarily disable this area of the brain.(16)


and reference (16) links to:


Snyder, A. (2009). Explaining and inducing savant skills: privileged access to lower level, less-processed information. Philosophical Transactions of the Royal Society B: Biological Sciences, 364(1522), 1399-1405. doi:  10.1098/rstb.2008.0290


The article describes experimental work earlier than 2009 in which savant-like skills were "artificially induced by low-frequency repetitive transcranial magnetic stimulation."

My guess is that almost ten years on induced savantism would have been explored further experimentally and either 1) refuted, or 2) more thoroughly proven and potential explanations tested with more complex experiments.

Has either happened?

See also this substantial answer from 2012.
There are no other studies I can find where TMS (Transcranial Magnetic Stimulation) was used in the same way, but there is a paper mentioning Snyder (2009) whilst discussing safety and other ethical considerations required regarding neural enhancement using noninvasive brain stimulation.

Hamilton, et al. (2011) said the following about Snyder (2009)(References re-numbered for formatting purposes and converted to APA style)


  Finally, one set of cognitive skills in which the role of TMS and tDCS has been especially controversial is the unmasking of so-called savant-like abilities. Snyder2 argued that inhibition of the left anterior temporal lobe (LATL) with brain stimulation interferes with semantic networks that normally impose top-down constraints on human perception—in short, making conception play a diminished role in perception. These investigators suggest that suppressing the LATL increases access to less-processed information, improving performance in perceptual abilities on tasks such as drawing, proof-reading, numerosity judgment,1 and other cognitive processes in which conceptual knowledge biases performance.3,4
  
  
  Snyder, A. W., Mulcahy, E., Taylor, J. L., Mitchell, D. J., Sachdev, P., &amp; Gandevia, S. C. (2003). Savant-like skills exposed in normal people by suppressing the left fronto-temporal lobe. Journal of integrative neuroscience, 2(2), 149-158.DOI: 10.1142/S0219635203000287PDF: http://howieswebs.ipage.com/pdf/savantskills.pdf
  Snyder, A. (2009). Explaining and inducing savant skills: privileged access to lower level, less-processed information. Philosophical Transactions of the Royal Society B: Biological Sciences, 364(1522), 1399-1405.DOI: 10.1098/rstb.2008.0290PDF: http://rstb.royalsocietypublishing.org/content/364/1522/1399.full.pdf
  Gallate, J., Chi, R., Ellwood, S., &amp; Snyder, A. (2009). Reducing false memories by magnetic pulse stimulation. Neuroscience letters, 449(3), 151-154.DOI: 10.1016/j.neulet.2008.11.021PDF: http://www.centreforthemind.com/publications/FalseMemories160109.pdf
  Oliveri, M., Romero, L., &amp; Papagno, C. (2004). Left but not right temporal involvement in opaque idiom comprehension: A repetitive transcranial magnetic stimulation study. Journal of cognitive Neuroscience, 16(5), 848-855.DOI: 10.1162/089892904970717PDF: https://www.researchgate.net/profile/Costanza_Papagno/publication/8506415_Left_But_Not_Right_Temporal_Involvement_in_Opaque_Idiom_Comprehension_A_Repetitive_Transcranial_Magnetic_Stimulation_Study/links/09e4150b4c7a9f03be000000.pdf
  


Regarding the safety of TMS, Hamilton, et al. (2011) said the following:


  There are known and possibly unknown safety concerns associated with noninvasive brain stimulation. The most important safety risk associated with TMS is the risk of inducing seizures. Since the introduction of published safety parameters for the use of rTMS, the incidence of induced seizure is exceptionally rare. All current evidence indicates that tDCS is extremely safe; its main safety risks are mild headache and a mild burning or itching sensation under the electrodes. Given the newness of these methodologies, one caveat is that not much is known about the chronic effects of either magnetic or electrical brain stimulation. Future studies may reveal unsuspected side effects and risks that are more serious than those associated with some conventional methods of behavioral cognitive manipulation (e.g., psychotherapy)....


There is quite a bit more on the safety and other ethical considerations, which I will leave you to read.

References

Hamilton, R., Messing, S., &amp; Chatterjee, A. (2011). Rethinking the thinking cap: Ethics of neural enhancement using noninvasive brain stimulation. Neurology, 76(2), 187-193.DOI: 10.1212/WNL.0b013e318205d50d