benignuman-
It would seem Rashi did see and use the Targum attributed to Yonasan ben Uziel on the Torah. In many places Rashi makes statements that have no source other than Targum Yonasan on the Torah. For example, Bereshis 4,15, Vayasem. Especially since Rashi changes from what Pirke R’ Eliezer writes there (21). -Lubavitcher Rebbe