Did you forget the file suffix .py for srt_tools/srt-resegment?

All of the tools don't have .py at the end (https://github.com/bricksdont/srt/tree/develop/srt_tools) - I don't know why the original author did it like this. Would you like to change that?

Ha, no, I did not know, then I suppose it's fine.

there are some problems with hyphenated and capitalized words, try it e.g. with the following original subtitles:
22
10:01:23,880 --> 10:01:27,640
Regelmässig nimmt er an Veran-
staltungen von FRAGILE Suisse teil,

23
10:01:27,720 --> 10:01:31,840
der Patientenorganisation
für Menschen mit Hirnverletzungen.

and with the special case when the first subtitle only contains "." like here:
1
10:00:00,080 --> 10:00:02,640
.

2
10:00:04,428 --> 10:00:06,360
Mit Untertiteln von SWISS TXT