Aircraft records a momentary speed fluctuation of up to VAPP +25
"Momentary" is the key. What's the Stabilised Approach max speed parameter? How long was the actual speed above it?
isn't it more dangerous to be flying into the decreasing headwind than the increasing headwind?
It could be seen that way, but on the other hand, an uncorrected increase in headwind could cause a balloon and a long landing.
The FOQA data in that outfit is obviously not confidential.