R&F JW's cannot partake of the emblems because they are not participants of the New Covenant, as shown by the type/antetype which says foreigners were not participants of the Law Covenant.
wt 98 2/1 p.19, par. 6 - "Further, other sheep lay hold of the new covenant just as foreigners of old laid hold of the Law covenant. In what way? Not by becoming participants in it but by submitting to the laws associated with it and benefiting from its arrangements."
Deuteronomy 29:10-15 destroys this JW dogma & its implications.
10 “All of you are stationed today before Jehovah your God, the heads of your tribes, your elders, your officers, every man of Israel,
11 your children, your wives, and your foreign resident who is in the midst of your camp, from the one gathering your wood to the one drawing your water.
12 You are here in order to enter into the covenant of Jehovah your God and his oath, which Jehovah your God is making with you today
13 in order that he may establish you today as his people and that he may be your God, just as he has promised you and just as he swore to your forefathers, Abraham, Isaac, and Jacob.
14 "Now it is not with you alone that I am making this covenant and this oath,
15 but it is with those standing here with us today before Jehovah our God and with those who are not here with us today."