sadly this will not = more tanks or less queue times for any other role.(i see no harm in offering this..but the attempt will fail to improve anything mark my words)
bribing never works.
only thing that possibly could, is complete revamp of party setup for 8 and 24 man content.
design all future content for 1 tank, 2 healers an 5 dps.

wow tried bribing players as well and it never improved queue times for dd or healers...ever.