It was still pretty stupid to not see that situation is the situation in 1915 and calling for a cease-fire and peace talks, stop right there, for the benefit of all sides.
There was no way that either side was going to budge when that was the status quo. When the Hundred Days offensive kicked off, and Germany was being pushed back on the Western Front, and with their home front on the brink of collapse due to blockade-induced starvation, they did indeed initiate peace talks.
They may have well known how many lives it would cost and did not care.