On it's face that sounds like a good theory, but it fails logically. Murkowski doesn't need to pander to anyone. She's not up for reelection soon, and she doesn't really have any credible challengers. A yes vote wouldn't have been a threat to her reelection chances in 2022.

If there's anyone in the senate that needed to vote no for reelection reasons, it's Heller of NV, where Clinton won pretty handily and he's up for reelection in 2018. A scripted vote would have had Murkowski vote yes and Heller vote no. 

She voted no by choice, consequences be damned.