I wound up with something like this (except $6 on AliExpress) and it works perfectly. Got a cheap USB 5v 1a adapter plugged into a timer. Huzzah, I don't have to restring the lot.
I have the solar panel lying on a surface face down just in case.
Thanks again for replying. Would you possibly be able to link something that would definitely work? I’m really confused
That plug is correct for my set. It slid right on and screwed tight. Didn’t work was the only problem!
Great news, I charged the batteries and the lights are working still. Phew
Sorry I have tried to read around a bit but can't seem to make any traction. I even bought one of these: https://www.amazon.com.au/dp/B0BP68NYKT?starsLeft=1&ref_=cm_sw_r_cso_wa_apin_dp_QT4BEAC0FVXXTKHXDWKV
But no good. There are a LOT of other models from the same manufacturer though that MAY...