Except you totally could still have Romani when Chaha's event was on, since you didn't have to finish the story to do it...
Whilst you could say so, the events and story are integrated in the timeline in a way that everything basically happens in the order of release; thus, when the event when Chacha comes around comes up, Romani is no longer there. In the case of someone who has yet to clear Solomon, it would be kinda like stepping into the future for a bit and then coming back.
Also, as the event this refers to [Halloween] happens in 2017, he's most certainly gone.
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