An RV can be designed to recharge from more than one source, but whether sources may operate together depends on the batteries, charging equipment and system configuration. Do not assume that adding another charger is automatically supported.
What needs to be checked?
Your installer should confirm that each charger is suitable for the battery type and system voltage, that its settings follow the battery manufacturer's requirements, and that the combined charging arrangements stay within the system's limits. The design also needs to account for any control or communication requirements between components.
Alternator charging needs particular attention to the vehicle and the charging equipment. Solar charging also depends on the panels and controller being a suitable combination. These are installation checks, not settings to guess from another vehicle's setup.
What should I expect to see?
Charging power can vary as the battery fills, when an appliance is running or when a source is limited. Different displays may report different points in the system, so compare the meaning of the readings before adding them together.
Use the documentation for your exact equipment and ask your installer which source combinations your installation supports.