it's not from a 1949 die! I went up the years and didn't find a "G" with the definite closing of the G on the right lower side, anyway "back from future" is not likely to happen for coins!
Then I went sideways downwards and found that the same G as yours is used on the 2 Pfenning coins from 1950. Now that doesn't explain anything, but it may be a base of trying to find why the 5 Pf G is different?
One step further down I have found your G on the 1 Pfennig from 1950!
Going upwards toward the 1950, where you have 2 different coins, your G is still not present, neither in the 10 Pf nor in the 50 Pf!
In the 50 Pf the G changes to your type in 1978.....
On the 1950 1DM you find your G, but how that correleates to your 5 Pf coin, I cannot imagine!
Take care and have fun
Ole
All in all it's a very good find and I cannot explain it at all!