Just distill the MDP2P as usual - the mercury wont come over during distillation. Also mercury-compounds so formed, wont distill over and if, you will get rid of them in the usual worup after the Al/Hg alylation. No reason to worry.
Discard the residue of the distillation in an environmental responsible way, say best is to bring it to some waste station, if not possible discard it down the drain and dont bury it somewhere.