There is an excuse. Political capital. It's not an excuse that is compelling, but this is Newsom. He's a Democrat that is trying to hold on to power for as long as he can, however he can.
Your comment makes no sense to me. It just doesn't track. Either he can parlay with pharma and point to how he kicked the bill, or he has to make excuses for not kicking the bill (regardless if he runs 2028 or not). It's political capital. It's power.
The point is that in the run up to the 2028 presidential campaign, Newsom isn't going to take any major actions which might alienate large swing voting blocs or major campaign donors (such as pharmaceutical companies). Unfortunately, low-income insulin dependant diabetics aren't a major political factor so regardless of what Newsom says in public, their needs aren't a priority for him.
Perhaps not solving the problem simply by allowing mexican medication, like New York doesn't simply solve pharmaceutical prices by importing Canadian drugs and keeping drug prices high in the present with promises of future fixes is a form of parlaying with Pharmaceutical companies