The events themselves are hard coded, but otherwise there is no issue - I just edited the display text in both event files and then some data text and there was no problem running my trusty Bare Geomod. There could be an issue if you edit the data text and the event actually takes place, but nothing further then a {localized_text} place holder.
The modding world of M2TW is full of advice not to mod in the main directory, and it has numerous reasons - ranging from inconvenience to outright complications. Hence why I developed my BG, that's apart from every edited file requiring the file_first entry anyhow. The exception being if you actually mod the main game and edit files that already exist.
There is a twist to string.bin files when you use Steam: new string.bin files will not generate for the 'terrible 4' (battle, strat, shared and tooltips) if you delete the old string.bin file - otherwise you should not have issues.
The link is to a tool that got released when M2TW had itself just been released and string.bin editing was still a bit of a mystery, keep in mind that the game only provides the string.bin files.
If you want I could have a look at your file if there is a formatting issue, but if you use
the BinEditor that shouldn't be an issue as long as you keep in mind that 'exporting' creates the TXT version and 'save' creates the string.bin version of the file.