It has been said that epsom salt does not change the pH (even though it has a pH of it's own). Salt can make other nutrients more available because it acts as a conductor. Epsom salt also has a lot of magnesium in it which is very good although I don't think magnesium is the real trouble since magnesium is a very mobile nutrient. When something is a mobile nutrient, then that means the plant can move it from one leaf to another. The plant thinks that making new leaves (up at the top of the plant) is the most important thing, so if the plant cannot get the nutrients it needs to gow those new top leaves from the soil, then it will take the nutrients from lower, older leaves and move those nutrients up to the new growth it is trying to make. sooo, the new growth will look ok, but the old leaves that had their nutrients sucked out of them will look not very good.
The lime is probably a good idea. Lime will change your pH and it also has calcium. Calcium is not very available when soil pH is so low (acidic). Calcium is not very mobile either, so that may be why the top leaves look bad; the plant cannot move the calcium that it does have. So it cannot bring that calcium up to the newly forming leaves. So it cannot build nice leaves there right now.
It would be good if you got lime recipes from somebody other than me because I have not used it yet. I use a lot of compost and compost is very neutral so my pH doesn't change unless I conduct an experiment or something. Lime is good for more than just changing pH too though. Lime helps in a few ways.
but Lime is very powerful. I recommend getting
at least three recipes before you use lime because recipes vary quite a bit sometimes and it is good to get lots of info before one makes up one's mind.
There is a forum here at this website that specializes in sick plants. You might go there and ask about these things so that you will get more input. And different websites are good at different things, I have not been to the sick plant forum that is here yet but I can recommend
www.hg420.com <<they are Very good when it comes to sick plants.
Other things besides nute problems can turn the top of a plant brown and curly...like lights that are burning it or maybe a pesticide that was used or maybe even bugs depending on how the brown is...I do believe the nute thing is a good idea though, since your pH is so acidic.
here are some charts that show nutrient availability at different pH levels
and a note of caution: there is an element called MOLYBDENUM and it is very dangerous<<<<NEVER ADD IT TO YOUR SOIL, only one ounce per acre is needed and any more or less can kill grazing animals
www.angelfire.com/cantina/fourtwenty/articles/nutrientavailability.htm