Its also just as likely that the van never broke down at all.... after all it's just left the garage, so Nick would be right on the phone screaming about refund or fixing gratis if it occurred even once...
Just like you wouldn't be pulling out ALL the relay switches if you didn't know which ones did which or which one had blown (if any). But you would be pulling them for the camera because it looks technical and then putting them back in because its easy drama, followed by pretend panic testing the engine to see if it'll turn over.
The long turn over and eventual rev up is down to low amps on the original battery and a tired alternator, no biggy, and the battery can be replaced to resolve most of your issues. And the light ups screen grabbed is what happens when a Mercedes crafter is switched on for the first time and a check before they all switch off, but of course if it really happened they've have that on video, but they cant since it didn't so a quick clipped photo is used to pretend the fault is there, where it isn't. it's also why Nick wont show the readouts on the diagnostic kit, as a plug in andscan would show the checks ok'ing and no fault codes which would expose his lie.
What this does do however is give them a get out clause to run back home at any point, if cornwall gets too scary for van living. Notice how they're cautiously skipping penzance and its content because they haven't done the research, to head to mousehole because its cheaper. Ideally you'd expect them to head over to the A30 now to do landsend and the first and last pub and the nearbyfarm and teashops. before heading over to St Ives and Hayle (which in their van will be fun!)
They've also missed the great content areas of Torquey, Paignton, Brixham(aka fishtown), Dartmouth and Dawlish all with their own secret beaches, lay over areas and bargin prices.
I suspect once they've done lands end and St Ives, they'll be darting back home asap, as they don't fully trust the van, or rather they cant cope with the confined space together for lengthy periods. They'll claim its a test run, or a van fault, but in honesty I truly believe Nicks just frightened of the roads around there, partly because his driving skills are that poor (and confirmed by the dents occurring prior and after the wrap).
Also nice to see more weight in the van lads... keep it coming!