I had a similar experience where I won an online Nascar race with a time difference of "0.000", when I examined the replay I saw a slight difference in distance from the finish line.
I guess the actual difference must have been less than 1/1000th of a second.
It is indeed very possible the distance was less than equivalent of 1/1000th of a second. If GT showed more than - say 6 digits - I'm sure you'd see a positive number (eg. 0.00000X) 👍.
I've been apart of about 4 of these. All won or lost by .000, some I've won and clearly won! but some I won but clearly lost also lost but should have won...
Pd is a mystery. Can't trust the replays I suspect! Or the line we see is slightly off of the actual timing markers.
Either way it was great racing and Id be happy with second, just for the "driving experience"