Get a gas or battery soldering iron! There is no way to re-attach it reliably without soldering that doesn't risk it shorting out, or burning up due to excessive contact resistance. Nearly all conductive glues are a waste of time
for something like this, and the high silver content ones that may work cost an arm and a leg and are only available mail order from specialist suppliers..
However, if I *had* to try to bodge it, the joint was near the board edge and there was enough space either side to minimise the risk of shorts, I'd take one contact + screws from a 3A screw terminal block, and cut a slot in the end of the contact just wide enough for the PCB so it could be slotted over the board edge and the screw tightened down onto the pad enough to make a good contact (Don't overtighten - as there is a hollow in the contact under the other side of the PCB, you will break the PCB). Clamp the wire in the other end of the terminal block contact as normal and insulate everything as best as you can!
Is the risk of shorting a fire hazard? I ask particularly because this thing is right by my bedding! I will take the fuse out when I switch off to be safe but have to get it up again asap because I have to use the internet/laptop every day to solve problems like the op.
Actually I will electrical tape it. It is nearly bedtime and looking into the tangle of wires for which one this is (ye I have not made it easy for myself with naming everything) at this time will be no simple task since they are all crammed behind the bed.
Btw what is the wooden board called where you screw all your devices to in the system? Is it it generally called circuit board as well? feels somehow wrong since I am used to that term only for pcbs.
This is actually a sorry state of affairs which must be rectified to tide me over as without my laptop my whole ecosystem will collapse. No access to internet is bad. Don't have access to mail order or local shops which will sell soldering irons right now as in a rural place.
One of my priorities on my list is getting some kind of mail solution but it isn't sorted yet.
I have had all sorts of electrical issues like lack of solar power but a tiny soldered joint was the last thing I was thinking about which would stump me!
So to get a way to solder the existing one back with limited tools will be the best way until I can get more exotic items ordered to prevent such an eventuality again. So perhaps the fire poker type of thing noted above.
Not sure what pointy metal thing I have around which will do the job though.
Open to suggestions for common items which I may have.
Will heating a fork with a lighter get it to hot enough to melt the solder blob to reattach the wire?
Getting some inspiration from this useful article:
https://kunkune.co.uk/blog/soldering-without-a-soldering-iron/Heating a screw looks like a good candidate.