I am debating between s5ii or go back to sony a7iv for wedding photography?

Hello everyone! I just switched from sony to lumix for wedding photography! Yesterday i did my first wedding woth Lumix. I also keep my sony a7iv for now with sigma 24-70. Yesterday i used equally s5ii + 85mm 1.8 / 35mm 1.8 ( lumix) and sony woth sigma lens. My thoughts are that sony in almost 100% accurate on subject detect and eye af. Lumix struggles a lot especially in low light. Lumix is very slow when start up and though the menu and photo previews. The image quality is comparable to sony. It's fine. Low light its ok. But sony felt faster more reliable and 100% accurate af. One more big problem is ghe flickering above 1/100 shutter speed. Sony doesn't seems to have the same problem. Does anyone feel the same? Should i go back to sony comptely? Is there any fix?