This is old news...Popasnaya was taken at least a week ago, and the Russians have moved on from there. Expect Krasny Liman and Svetlodarsk to fall shortly, while the encirclement of the main Ukr army at Severodonetsk continues.
The problem for Putin is that even if a few thousand Ukrainian troops are encircled (and that’s a big if) what difference would it make?
Ukraine is mobilizing a force of two million. Supplied by foreign grants that are larger than the entire Russian military budget. Long term Russia has no path to victory.