As for your question about long crank times, could be a fuel pressure regulator or anti-backflow valve in the fuel pump or a leaky injector. The pressure gauge will tell you IF it is a leak, but not where.
The clip looks like a retainer for a fuel, vapor or brake line.
And THIS points to a charging system issue. Unless your fiance is pounding out tunes thru a huge aftermarket amp or running the seat heaters, idle should NOT run the battery down.