Yes, you're absolutely on the right track - your testing clearly points to a PCM failure in the ground switching circuit for the drivers side coil bank. The fact that you have +12v but no ground pulse during cranking confirms the PCM isn't completing the circuit.
Your unprogrammed Ford F53 transponder keys will continue working indefinitely, but they lack anti-theft security features. Programming adds immobilizer protection but isn't required for basic operation.
For 50-amp RVs, invest in a quality surge protector like Progressive Industries EMS-HW50C (hardwired) or EMS-PT50X (portable). Hardwired units prevent theft and provide superior protection, while portable units offer flexibility but require security measures.
Class B offers better MPG and easier driving but limited living space. Class C provides more comfort for extended trips. For 40-50 mile cycling days, Class C comfort may be appreciated. Consider small 24-27ft Class C for balance.
When your Fleetwood Bounder's ignition switch isn't getting power despite good fuses and relays, check the ignition feed wire from the battery junction box, inspect the main power distribution connections, and test the starter relay circuit which often feeds the ignition switch.
You can replace your 2003 Four Winds Hurricane ignition switch yourself without special tools. Modern ignition switches typically use simple mounting clips or screws rather than the old steering wheel puller tools.
Ford V10 Fuel Pump Driver Module FPDM on Allegro Bus is on driver side frame rail near fuel tank. Small black box with single connector. Common failure point causing starting or stalling issues.
A hard-to-turn ignition key in your 2007 Fleetwood is typically caused by a worn ignition cylinder or key. This is a moderately challenging DIY repair that requires disconnecting the battery, removing the steering column covers, and replacing the ignition switch cylinder.