French language Q&A Forum

In the writing challenge "Les noces d'or de mes grands-parents" the phrase "Et ce qu'ils se sont déclaré était tellement émouvant" appears. Why is there no plural agreement on the verb "déclaré "?

It sees to be the same case as this example in the lesson "Conjugate reflexive verbs (+être) in Le Passé Composé (conversational past)":

Elles se sont disputées = They had an argument.

Is it because the verb has an object which precedes it and the rule of agreement with a prior object takes precedence over the rule of agreement with the subject?

Something like case 3 1/2 here:https://www.lawlessfrench.com/grammar/agreement-with-pronominal-verbs/