It's incorrect to say that Ralph used a pocket knife to open the trunk in the black Hyundai. Car manufacturers have been required to install glow in the dark emergency trunk releases in trunks since 2002. Ralph is smart enough to know this as well. Also, Ralph's kidnapper should have known that the trunk was open as most modern cars have an indicator that indicate when doors and/or the trunk is open unless he was too distracted to notice the indicator light on the dash.
Toby says "Even if Wally & Timbo become BFFs forever there's no getting around the fact that Scorpion is Walter's team." The term BFF stands for Best Friends Forever so adding forever after BFF is a tautology - what Toby actually said was Best Friends Forever Forever.
When Walter is setting up the can of bug spray to explode, Tim reaches in his pocket for his lighter before Walter asks for it.