Normal mode DNA

[OddApplaud]

I've been stuck on the neurax worm on normal mode for quite a while
Mainly because the transmissions, symptoms are different from the usual

Here's the problem I run into
-During the stage for lethality
-I'd start to not gain any DNA
-Devolving would cost and not refund me anything
-I'll Be able to evolve 1 symptom with low lethality and lose due to the cure

I would appreciate some DNA conserving tips