Apple logo shows for ~3 seconds, then screen goes black (LCD on)

Client states another individual replaced the battery, after which the screen stopped working (it seems they broke the digitizer during reassembly). I replaced the screen. When this iPad mini 4 is plugged in, the apple logo displays for about 3 seconds, and then the screen goes black (though the LCD stays on).

Cannot enter recovery mode. Device does not power on at all when not plugged in.

Any thoughts? I’m thinking the replacement battery the other person put in may be defective but don’t have another on hand to swap in.