Fixing my worktunes question, thanks!

I have a few pairs of worktunes that have stopped working. (I kept buying new ones instead of trying to fix them) One of them I opened up and pushed the battery plug back into place and it started working again but the other two still aren't working after that particular fix, and it doesn't look like any of the wires have come loose from their solder connections. Do you think buying a new battery and swapping it out with fix them?

They are 100% unresponsive, no blue light when charging, nothing happens when I hold the on button.

Thanks for any insight!