Gadolinium is not used in any CT contrast I am aware of.
Iodine compounds are used, and there are also several of those that are quite a bit better than others.
It has been in the past, who knows. Nobody told me who the manufacturer was or what it was made of. It could have been (Magnevist) gadopentetate dimeglumine. Magnevist, that sounds like it would be healthy for you too. /s I seriously doubt it was Iodine that destroyed the muscle tissue, more likely some heavy metal of some kind.
https://mriquestions.com/gadolinium-on-ct.html