Bamboo GTR1: VESC conversion questions

Hello all, I'll put the short version here at the top because I tend to ramble:

TL;DR - Does anyone have any experience with the process of swapping this model (or any model with identical enclosures for the battery pack/BMS/ESC to a VESC system? I am aware even the smallest popular VESCs/BMS are usually too big for existing enclosures. Any major considerations to be aware of, any documentation you may have saved/posted (I could not find any in searching here or elsewhere), tips on where to get battery enclosure/ESC enclosures or spacers required, whether I can keep the existing battery pack attached to that giant PCB, etc.? And thank you so much to anyone who might have advice

Ok here's the full version:

I've recently been having issues with a Bamboo GTR series 1 I bought for $250 on Marketplace. When I bought it, remote was disconnecting (but staying on) every few seconds of riding. After disassembling it and poking around, I learned it was because the wires on the power button had come loose inside of the heat shrink, so I re-soldered it and fixed the issue. (By the way, I've seen posts from others having similar issues, definitely pass on the info if you see another of those, board powering off frequently while remote is staying on, it could be the cause.)

A month later after 100+ miles of super fun rides, and riding on wet roads a few times (my fault) the motors started acting weird, uneven torque, wobbling rear truck, and would only accelerate for a few seconds at a time unless I was going very slow. With the board flipped upside down, they rattle and make crazy noises, but one more than the other, and same issue, stops accelerating if I pull the trigger beyond like 10%. I wanted to try to take the motors apart to see if maybe a magnet or sensor had come loose, but I was not able to get the grub screws off due to the Loctite, I know about the soldering iron and MAP torch tricks, didn't at the time, haven't tried it yet but now I have a different issue.

Now it seems like I've messed up the ESC. I was watching a video by Evolve about motor diagnostics featuring a different model where they swapped some JST connectors on the ESC, clearly those JST connectors were meant to be disconnected on that model, but not on mine so I pulled a little too hard on a hard-soldered connector and pulled a few wires loose, had to solder it back together and now one motor isn't spinning. (I'm aware NOW that I could've just swapped the damn motor connectors, I did a very big dumb).

I will continue to try to double check my soldering job and see if I can fix this, however, I've already been wanting to switch to a VESC anyway, and I just wanted to know if anyone has done so on this model or one with the same enclosures (Bamboo GTR1 seems quite different from the Carbon equivalent, not sure if it has the same enclosure as other board models?) or has experience with it? I know FlipSky is a popular brand, but I also know that their standard dual 4.20 model, the smallest they have, will not fit into the existing enclosure, it needs at least ~10mm more clearance if their measurements are accurate. I also don't know if I can keep the battery pack with the giant PCB attached if I do this, I assume I can and just have to do some custom wiring.. but IF not, due to the little ribs in the battery compartment of the enclosure on this model I would have to make a custom battery pack in sets of 4x2 and wire them together, or buy, or get a custom enclosure 3D printed.. I think that won't be necessary but if I'm wrong and anyone knows, please lmk.

If I am not able to fix my ESC, let alone the motors that are misbehaving, I will have to go the DIY route because I simply cannot afford to replace the ESC and both motors with official Evolve parts right now. I'm poor, hence being a DIY-er and risking a faulty board for $250

Again, thank you so much if you have any advice. If not, thanks for reading anyway