1:30, you should have Up-Bed early for a chance of at least landing on stage.
1:40, honestly it's important to expect MK to come back onstage with Tornado. It will really mess you up if you aren't ready for it. If you want to cover as many options as possible, U-airing usually is the best bet. Dash attack however can beat it on reaction. The next time he did Tornado, I do have to commend you for trying to F-smash him out of it, although it was mistimed. It's usually easier to D-smash it iirc since it's more disjointed (but doesn't reach as far since G&W doesn't lean forward on it), but Dash attack is the most consistent option.
If you're going to spotdodge in general, usually you should Jab or D-tilt or grab. There really isn't any other point to spotdodging with G&W especially in this matchup. At around 2:00 you got punished for trying to spotdodge -> D-smash. It really doesn't work except against terrible characters lol.
2:26 you got Up-B gimped again. Only in this situation you probably should have attempted to recover high. Next time he Tornadoed you DID D-smash him out of it. That was smart and what I would have recommended.
*skips the 2nd match partly because you won it, partly because I'm too lazy to think about the stuff that can happen on CP stages*
Don't just D-throw D-smash against MK. You have other options (and NEED to use them when he techs as well). I've been trying to get more G&Ws to iDA after D-throw. It's really good honestly, since it puts them in a position you can follow up off of pretty easily at low percents.
if MK is edgestalling, just D-air him. Don't slowfall it. That just occurred to me around like 16:45 I think.
Otherwise I dunno what else to say. MK's options for getting grabs are indeed stupid, and really all you can do about it is play footsies with D-tilt and Jab and your own grabs.