Can I save them

I left my girls for 3 nights 4 days and had my bro in law look after them during my time away. I left him with complete instructions on what to do but when I get back I believe I have lost 6 outta 8 and they are now 25 days into flower. They are literally brown and dry as if they were sprayed with roundup except for right at the stalk and the flowers that have started.
He says he only watered them once but I believe he possibly sprayed them with some nutes, honestly I have no idea.
I am gonna try and flush them with alot of water to see if I can pull them out of what appears to be death.
If anyone has any suggestions, let me know. Also a couple of weeks ago my temps got really low due to below zero temps outside which caused a drop to at the lowest about fifty but with extra heaters and monitoring I kept an average of around 60 with lights off.
My clones were fried to when I got back, but my mother plant is still perfect that is why I think it was he because he told me that he didnt do anything with her.
She looks perfect, and everything else is well possibly a very big loss.
Okay I am rambling if anyone has suggestions please let me know.
If flushing, revegging, killing and starting over, or whatever is something I should do just tell me.
I will get some pics on here shortly to let you see what I have left.
thanks RIU

I got the best pics I can, its actually during my dark cycle so maybe I can get some better tonight. As you can see mom is doing well, and that is what they all looked like at the first of the month. The cold spell did make the me think at one time that they were stressing but as soon as temps warmed up they came back around. Then I leave this weekend and well....

they look poisoned and obviously dead.
mother plant looks a bit overfed.
start a new batch you must.

You are right they do look poisoned, as if someone watered with gasoline, I dont get it.
As far as mother plant the only feeding she gets is in the soil.
She justa fat mama I guess.
Have already started new batch, also bout to start a few seeds...
thanks

Honestly dont know what to kill first bro in law or plants,
guess plants are dead...

Gone only 3 days? WTF did he put on those plants? I think he aims to put you outta business for one reason or another.

he says just water and that he didnt even put any only leaves, but WTF is right.

this is my 3rd grow, I have always used the same water, from the same place, and prepared the same way.
It has never killed them, and it is same water that mama is drinkin, I just dont get it.

man this sucks

my hands would be around someones freakin neck...looks like high temps and no water.


thats drug abuse...

did u check the run off water that would have gave u an idea what happend. u should only try to save the ones that look green still some look like u can save them but will lose some grams the somke will still be good.flush with only fresh 7ph water and check the water running out the bottoms.if it is under 6.3ph to much ferts.whiis okch makes the ph off that will kill them too .water should go in at 6.8 to7.0 and come out at like 5.9to6.5 which ok . put alot of 7.0ph water through them and wait 2-3 weeks see if they pull out of it.