I think they don't want to increase fuel prices so will quickly try to clear their cases and dissolve assembly. Only way to avoid getting punished for high prices I guess.
Fuel prices or economy is a non issue but they framing it to avoid the real situation on the ground in result of the regime change.
Both General's establishment and the US are at risk to lose big if the situation goes out of hand on the street. Already the public has opened up against US and generals and it will take long time to overcome these sentiments even if Generals agree to elections. The generals cannot deliver much to the US in such circumstances.
PDM's top leadership is a tool for regime change and . they have a limited agenda regarding their cases, wealth and some issues of political survival and political inheritance. Pakistan, the current government and economy are not their core issues. The US and generals will dump them whenever they felt it necessary.
Of course, the middle tier leadership has vested interests in Pakistan but their top leaders are in it only for their personal reasons.