Not necessarily. If the dev that created the TemplateVars added that suffix for easier identification, then it was a good way to find them quickly, but it is not a direct flag as you can change the TV settings and not change the name.
I suggest the following:
Check all your TemplateVars to confirm that all are set properly - The problem should not be here.
Check your Migx configs and confirm that all your formtab fields are having the attribute InputTV (even if set as empty). Example of a field:
I’m still lost, so I’m going to start from the beginning and learn from scratch, rather than attempt to fix someone else’s build without any knowledge of how MODX actually functions.
The tvs names can be anything, maybe the original dev used some structure but it is not necessary at all. Because MIGX will often use multiple tvs it would seem to be rare that putting migx in the name would be helpful, more commonly the name represents the data contained in the tv.
You should be able to track the tvs that are in play through the template you are using, they will be called directly in the MIGX call. There can be other ways of pulling stuff in though, Modx is really flexible so there’s always another way to do something.
It is hard to reverse engineer someone else’s system due to this, but with MIGX is shouldn’t be too tough I would think. Still, starting from scratch can help a lot