The aerolasticity issues were an initial problem for other armament, particularly the early cannon installations as nuuumann correctly said. It wasn't the only problem with the installation, but this isn't the topic here. Suffice to say that the shell ejection system was also contributing to the jams. The main spar was modified and if some skins were altered (I can't find a record of this) it would seem entirely reasonable. As I've said many times in many threads, "just" doing something to any WW2 aircraft is invariably a lot more difficult to do than to write!
When the heavier armament was adopted, whilst the aerolasticity of the wing may have been a consideration it wasn't the major factor in determining the position of the cannon/MGs.
Cheers
Steve