FinalNode must not have outgoing ActivityEdges — model validation fails on activity final node

I am modeling an activity in UML 2.5.1 and my validator flags the model as invalid when an activity final node has an outgoing control flow. My understanding is that the Activities clause defines a well-formedness rule: a FinalNode (both activity final node and flow final node) must not have outgoing ActivityEdges, and violating it makes the model non-conforming rather than merely stylistically wrong.

The design intent was to let one branch continue after another branch reaches a final node, which I now suspect conflates the activity final node (terminating all flows in the activity) with a state machine final state, where entering the final vertex completes the region and can trigger a completion transition on the enclosing composite state.

Constraints: the model must validate cleanly under a conforming validator (Eclipse Papyrus), and I want to stay within the UML 2.5.1 specification rather than rely on tool-specific leniency, since validators differ in strictness.

• Does the FinalNode rule apply identically to activity final nodes and flow final nodes, or only to one of them?
• If a branch must continue after another ends, is a FlowFinalNode on the ending branch plus a merge/join on the continuing flow the conforming pattern?
• Is a validator that accepts the outgoing edge simply non-strict, or is the constraint scoped differently across 2.4.1, 2.5, and 2.5.1?