Indeed, the Latin verb "confabulor has the meaning of "discuss, converse" [0], not specifically "inventing things", and Romance languages already have words derived in sound and meaning from this classic Latin sense. For instance French already has "confabuler" meaning "speak familiarly with someone" [1]. Thus in Romance languages, this proposed usage of "confabulate" imported from the psychiatric word could be understood poorly due to preexisting similar-sounding words that do not include the notion of "making things up".
Just proposing thoughts here, not advocating for a final decision. Maybe it's still good to adopt this wording!
[0] : https://en.m.wiktionary.org/wiki/confabulor#Latin [1] : https://www.dictionnaire-academie.fr/article/A9C3479