Any info on what the current salaries are for our former Illini players now overseas?
Hard to find info on specific players other than the highest earners, because no salary cap means teams don't have an obligation to report, and interest in basketball salaries isn't has high as for soccer so journalists don't bother to track down or report the data for every player. There are several sites that report typical or average salaries based on surveys of players. This one puts the Greek League typical salary range as $60k - $250k.
https://www.josecolorado.com/overseas-basketball-salaries
The Adriatic League, where Trent plays, is around the same tier of league, so it's probably similar. The team also matters a great deal. Bigger teams, especially those who compete in EuroLeague, have much bigger budgets. Trent's team finished 6th out of 14 in the Adriatic League last year, so they're a good team, but not one of the top spenders (those would be Red Star and Partizan). They don't compete in EuroLeague, but are competing in the Basketball Champions League, which is much like the Champions League in soccer except that the existence of the EuroLeague (which is not run by FIBA Europe) reduces the prestige (and $$$) pretty significantly. Lavrio, Plummer's team, finished 10th in the Greek League (out of 13) and are thus not in any European competition this year.