I don't see how you tiered up by playing coin room games
None of the stats are saved in such a way that we can view all of them. That does not mean WGT does not have or use something in connection with some way of determining coin rooms success.
This is the third instance I have heard about recently that only coin games can be considered as the factor that pushed each person over into being promoted.
Whether it is win rate, along with coin room bankroll, among other possible factors. WGT has said nothing regarding the determining factors, but it is clearly happening.
If win rate's against higher tier players is used in some fashion, will they also base it on whether the higher tier player advanced using red tees and has no experience playing mobile? I don't know.
But there are more variables to coin games than just tier... and beating a higher tier player doesn't necessarily mean that same player will be highly competitive in non apparel WGT tournaments. Some will, some may not... it depends on whether they specialize in one format or both.