10kW seems like a capacity that could be carried in the truck bed and then set up on flat ground while camping out.

A realistic daily average output would be 30-40kWh in a day, or about 1/4 of the truck's battery capacity. Sunny days in summer would do better, cloudy winter days would do worse.

Recharging fully in 5-7 days seems reasonable. Assuming you actually had drained the battery to near empty and were needing to charge it back to full.

By some comparisons that seems slow. But it might be faster than waiting for a gas truck that never comes.