Translation:I saw that, even ill, she keeps her dignity.
In this sentence, not much.
"I saw" is an on-going action in the past. We don't know if it has finished or not now in the present. It is the past looking at its own present.
"I have seen" is a completed action now in the present. It is the present looking back at the past.
Better English? I've heard of keeping dignity many more times than I've heard of guarding it.
There are lots of ways to translate this. It rejected "i saw that even though ill she maintains her dignity". Reported 29 May 2018.