It's certainly an intriguing passage, isn't it? Whether or not the elders of Israel were in the presence of Jesus, the second Person of the Trinity, we of course cannot be sure, but personally I have my doubts; the text lacks all the regular earmarks that exist in the OT when the faithful are being visited by some angelic being who later turns out to have been God.
Something of which I think we can be a little surer are the parallels that exist between this strange encounter and the last supper. In Exodus we're told that there was "set upright twelve large stones to represent the twelve tribes of Israel" (Exod 24.4). Then we have burnt and peace offerings being made and Moses sprinkling the sacrificial blood on the people of Israel and declaring, "This is the blood of the covenant which YHWH has made with you in accordance with all these words" (Exod 24.8), whereupon the elders ascend the mountain and eat and drink a covenantal meal in the presence of God in order to ratify that covenant. Later we find the twelve disciples of Jesus eat and drink a covenantal meal in his presence (in an UPstairs room?), where he declares, "...this is my blood of the [new]* covenant, shed on behalf of many for the forgiveness of sins" (Matt 26.28).
*Although Matthew doesn't specifically say that this is a "new" covenant, Luke does, and some extant manuscripts have added "new" to the text, probably to harmonize Matthew (and Mark) with Luke.
