SimpleX is only attended by the core admin who is not always online and doesn't have it installed on a mobile device (which might change later).
I think you should add this information for SimpleX on eXch website.
From my experience I tried contacting eXch support with SimpleX chat using link that was provided, and nobody accepted my request or answered anything.
Liquid network is a next project we will list and there is currently work ongoing.
Great to hear this!
I hope you are going to add both L-BTC and L-USDT, this will be good alternative for using stable coins on tron and similar chains.