Laser and electrolysis are not the same thing.
If she had proper electrolysis treatments and followed the treatment schedule the electrologist recommended, those follicles that were destroyed did not come back to life, they can't, it's impossible.
If she had laser treatments, there is a possibility of stimulating hair growth on women's faces. Laser hair removal is still considered a fairly new field, and scientist are just now beginning to study what is known as "Paradoxical hypertrichosis after laser epilation." The reason for this phenomena is still unknown. It has only presented on women's faces and men's upper arms and shoulders. In most cases, the patient's hair was not coarse. Laser hair removal requires very dark, coarse hairs to be successful.
We are born with an average of 1000 follicles per square inch of skin. A man with a full beard has fewer than 100 active follicles per sq. inch. That's more than 900 inactive follicles in a square in of skin. A woman who has what professionals classified as a "full beard" has about 60 active follicles. That leaves many unused follicles to come to life at any time. Any woman who has that much hair on her face has a hormone imbalance.
There are many reasons your mother could be producing new hair. Germans aren't actually known to be hairy. Although they used to be known for not shaving. In Europe, those genetically inclined to have hair are in the Mediterranean countries, such as singlemamma above who is part Sicilian. But it is possible that she has more than German in her heritage.
Menopause creates hormone imbalances and unwanted hair growth for most women. Many medications cause hair growth. Frequent surges of adrenaline (a hormone), such as during periods of stress, can cause hair growth. PCOS, insulin resistance, diabetes, and many other conditions have unwanted hair growth as a symptom.
If you mother saw an electrologist, and the electrologist didn't recommend that she see an endocrinologist, then it is probably a normal, yet annoying, amount of hair.
Laser hair removal technicians are not required to have any training in the biology of hair and it's causes, so if she saw a laser tech rather than an electrologist, she may want to get an electrologist's opinion to find out if the amount and pattern of growth is normal or indicative of a potential health problem.