As noted in the commentscomments, a paper [1] of Garoufalidis, D. Thurston, and Zickert answers this question for $\operatorname{SL}_n(\mathbb{C})$.
[1] Garoufalidis, Stavros; Thurston, Dylan P.; Zickert, Christian K., The complex volume of \\(\mathrm{SL}(n,\mathbb{C})\\)-representations of 3-manifolds, Duke Math. J. 164, No. 11, 2099-2160 (2015). ZBL1335.57034.