You nailed it!

When you move to a stronger light, it's like moving to outdoors.
You must Harden them off by doing it gradually.

Under low light they grow extra leaf mass to capture that light.
Because of the low light, root growth is less aggressive.
Less water gets moved so the roots don't have to proliferate to keep up.

More light causes them to try to transpire more rapidly than their present root system can support.
You have seen the result. They look exhausted, yah?
If you can't raise the lights any higher, removing 10% or so of the fan leaf will have the same effect as raising the lights.
Then slowly increase the lighting as the roots grow to meet the challenge.

I give them a day or two of shade when I move them outdoors.
And, since I filter out the short wavelength UV in my greenhouse, that's all it takes.

Aloha,
Weezard