Russia Ukraine negotiations fell apart in early April and Russia didn't leave Snake Island until the end of June. The two events have nothing to do with each other.
The good will gesture I was talking about was Russia pulling back from their encirclement of Kiev in late March which coincided with the tentative agreement they had reached with Zelenski until the US/UK stepped in and scuttled it, not some meaningless evacuation from an island of little strategic value months later.
That wasn't a goodwill gesture, that was the Russian army floundering in the absence of adequate logistics to support what they incorrectly anticipated would largely be an uncontested road march. Instead they got smoked at Hostomel and couldn't generate further advance after trying to bypass Sumy and Chernigov. Their effort was doomed because they couldn't support armies on that many axis at once. That's why they retreated.
Anyone reading Russian retreats as 'goodwill gestures' has laughable appreciation of history and/or military realities.