Macbook Pro 13" 2019 switching off when not on charge

I need help, in a big way.

I started a week ago, my computer started turning off randomly around at 70 - 80% battery. I would turn on again when plugged in, stay on when unplugged, then it would only be a matter of time before it switched off again.

I have:

1) Reset the PRAM

2) Reset the SMC

3) Run Apple diagnostics

4) Used the Battery Health app, which reflected the health of my battery as 80% at 350 cycles and in normal condition. As did the OS.

5) Replaced a slightly damaged charging cable

None of this did anything to help. What's more, is the battery was not only dying at higher numbers, sometimes it would last till about 30%, baiting me into thinking the problem is improving (insert clown emoji).

So today, I tried another SMC reset and I did a Safe Boot for the first time. Now, the OS and coconutbattery (decided to use another app because at this point I need all the perspective I can get), says re: the battery A) condition: replace now, and B) macOSbattery status: poor. And what's even better, now the computer won't work for a second without the charger.

I know the easiest and most painless thing to would just be to replace the battery, wipe the computer, and reinstall the OS (scorched earth). But I have them 32-bit apps, so me and Mojave won't be breaking up so soon.

Other potential fix seems to do a re-calibration, but from all the information I've provided could you please tell me:

A) Would a re-calibration solve the problem?

B) What problems are you picking up on? A more intelligent person than myself said "it looks like your intelligent battery monitor got messed up somehow" but I have no idea what that means, or what to do next.

*Fun fact: Works perfectly while on charge, and no amount of SMC resets are helping.

I will attach the coconutbattery report in case that helps any wise, noble, brilliant, good samaritan offer some kind of insight into what the problem could be. And I'll also attach the MacOs report for good measure.