Ann: Silver Lake and Doray Merger Presentation, page-52

Don't you think that a gold spike will help the SLR gold price as well?
Unless a rival bid emerges or DRM finds a rabbit jumps out of the ground to force them to announce revised reserves/resources - very unlikely in the circumstances, then why should DRM/SLR need to revisit the agreement?
Face it peoples, the two Boards have come to an agreement for a merger on the stated terms. There needs to be a substantial change in circumstances for there to be a majority vote of shareholders to change this and gold price will not provide it. Unless the Boards are idiots, they will have secured majority support for the merger before announcing it.
BTW, SLR SP shows that their shareholders and the market are not impressed by the merger either. That probably means that it is a reasonable merger with both companies on more or less even terms.
I suggest that is better to evaluate what the resulting benefits to each side may be and try to assess the overall outcome for the merged company going forward.