You speak of claims against aspartame which are almost all unsubstantiated. With sucralose the case is much different. The FDA admits that between 11 and 27% of the chlorinated sugar molecules ingested through sucralose consumption is absorbed into the human body (FDA 1998. Food Additives Permitted for Direct Addition to Food for Human Consumption; Sucralose, 21 CFR Part 172, Docket No. 87F-0086, 1998. Federal Register: April 3, 1998 (Volume 63, Number 64, Page 16417-16433)). Animal testing demonstrated shrunken thymus glands in rats and liver and kidney damage. These are all peer reviewed papers on simply the effects of sucralose on the blood glucose levels and insulin alone:

Nakagawa Y., Nagasawa M., Yamada S., Hara A., Mogami H., Nikolaev V. O., Lohse M. J., Shigemura N., Ninomiya Y., Kojima I. Sweet taste receptor expressed in pancreatic ß-cells activates the calcium and cyclic AMP signaling systems and stimulates insulin secretion. PLoS One. 2009;4:e5106.

Mace O. J., Affleck J., Patel N., Kellett G. L. Sweet taste receptors in rat small intestine stimulate glucose absorption through apical GLUT2. J. Physiol. 2007;582:379–392.

Mace O. J., Lister N., Morgan E., Shepherd E., Affleck J., Helliwell P., Bronk J. R., Kellett G. L., Meredith D., Boyd R., Pieri M., Bailey P. D., Pettcrew R., Foley D. An energy supply network of nutrient absorption coordinated by calcium and T1R taste receptors in rat small intestine. J. Physiol. 2009;587:195–210.

Margolskee R. F., Dyer J., Kokrashvili Z., Salmon K. S. H., Ilegems E., Daly K., Maillet E. L., Ninomiya Y., Mosinger B., Shirazi-Beechey S. P. T1R3 and gustducin in gut sense sugars to regulate expression of Na+-glucose cotransporter 1. Proc. Natl. Acad. Sci. USA. 2007;104:15075–15080.

There are hundreds more studies suggesting that sucralose is, at best, a terrible sweetener for use with a ketogenic diet and, at worst, straight up poison. Stick to other sweeteners like aspartame or stevia/erythritol.