I somehow got it to work using 2 3Commas accounts. I swear it wasn't taking all the correct entries and exits before with 1 account, but maybe I made a careless mistake somewhere. I was already using 2 bots as well, but now each account has 1 bot.

I use 6 messages: long entry, long take profit, long stop loss, short entry, short take profit, and short stop loss. I could probably get away with using 4 messages, but I like the option to customize the take profit and stop loss messages if I needed to. Then, I used the info in their doc I linked in my post and inputted those messages into the long entry and short entry.

I use a single alert and have {{strategy.order.alert_message}} in the message section of that alert.

It managed to close a long early in one account and open a short in the other. Maybe the mistake was that I previously didn't add a delay or something which could have prevented let's say a long opening in my trading account if a short was already open.