Psalm 78/Notes/Grammar.V. 11.741627
From Psalms: Layer by Layer
Following most modern translations, it may seem preferable to limit the relative clause to modifying only נִפְלְאוֹתָ֗יו, light of parallels such as Mic 7:5 (כִּימֵ֥י צֵאתְךָ֖ מֵאֶ֣רֶץ מִצְרָ֑יִם אַרְאֶ֖נּוּ נִפְלָאֽוֹת). Nevertheless, qal ראה is also found with עֲלִילָה in Ezek 14:22 (וּרְאִיתֶ֥ם אֶת־דַּרְכָּ֖ם וְאֶת־עֲלִֽילוֹתָ֑ם), so there does not seem to be a good reason to exclude עֲלִילוֹתָ֑יו from the scope of the relative clause.
For the alternative position of the prepositional phrase "before their fathers," see the following note.