Definitely and that’s not incompatible with what I’m saying.
You are indeed looking far back to the Proto-Indo-European where words are very different and sometimes a bit of guesses.
If you look at the whole tree, you will see that both trust, truth and true share common Germanic roots (that’s pretty obvious by looking at them) which is indeed linked with words meaning “solid” and then “promise, contract”.
What’s interesting is that the root is shared between “truth” and “trust” while in French it’s not (vérité from veritas vs confiance from confere).
Would you mind sharing your reference on that? All the etymology sites I rely on seem to place the root in words that end up at "solid" or "comfort".