I'm glad you're okay. It's hard to make out much because of the fire extinguisher residue, but you can clearly see the middle of the cowl, brake reservoir, and air filter housing are melted so that's probably around where the fire started. I think fuel or brake fluid most likely caused the fire. Brake fluid is very possible if the cap wasn't properly twisted on. Anyone that has removed it to check their brake fluid knows how difficult it is to get it back on. The fuel lines are in that area too so a fuel leak is also possible, especially if that line with the pressure sensor was recently serviced and not properly reattached.
Be sure to submit a complaint with the NHTSA. Stellantis might investigate the incident if you reach out to them. Please do post back and let us know what the cause was when it's discovered.