GMGMQ or the original GM shares are the bankrupt company. It only has any value if the shareholders file and win a lawsuit (highly unlikely). When it emerges from bankruptcy, the new company will likely be privately owned with the US and Canadian governments owning about 72%, original bond holders holding 10%, and the UAW holding the remaining.
If in a few years, the company becomes profitable, new shares will likely be floated on the market.
The GMGMQ shares will be worthless since it doesn't own the reorganized company.