I've got some good news and some not-so-good news for you, UnconformistSheep. The good news is Mario is Missing has already been
approved for release on Abandonia, so if you'd like, you can post in the
Offers section and offer to donate a copy of your disks/CD-ROM (whichever you have) for Mario is Missing to Abandonia.
The not-so-good news is I wasn't able to find any information on the DOS version of Mario's Time Machine. However, since it sounds like you have the floppy disks or CD-ROM for the DOS version of this game, can you please confirm you have the disk/CD-ROM for Mario's Time Machine? This way, I can make a final determination on the abandonware status of the game. Thanks!
Also, Just as a friendly reminder, if you want to ask about multiple games in the future, please create separate posts for them. This is because the fine staff (including me

) of Abandonia need to be able to easily sort game request posts by their status: Approved (can be put on Abandonia), Rejected (temporarily rejected because the game is still protected, still sold, etc.), and Invalid (permenantly rejected because the game will be sold until the end of time on Steam, Impulse, and similar online stores, the game was never made for DOS or Windows, the game is permenantly copyright-protected, etc.). For more information, please check out the
Game Request Rules & Important Info thread.