Taking Mr. Monster's invitation to "look up" Justin Tabb...
So, it would seem that Mr. Tabb came in with Amplifx, whose home page is amplify.io, and whose Twitter account is suspended - at least the one linked from their website is (Ampexchange). There is another Twitter account called RealAmpExchange, with 14 followers as of this posting, but that one is not linked from their apparent website. Mr. Tabb's personal Twitter account appears to have been deleted, judging from mentions of it in other tweets. Another of Mr. Tabb's business ventures appears to be Substratum.
In 2018, Mr. Tabb was involved in a lawsuit involving disputed claims about software development, and which action was ultimately settled. <
https://www.courtlistener.com/docket/6630369/fntech-inc-v-tabb/>
If one searches Twitter for mentions of "Ampexchange" and "Tabb" or "Substratum" and "Tabb" one finds lively conversations about those projects and the persons involved. Of course, one can find lively conversations about all kinds of things on social media, so one is left to one's own hypotheses in the absence of any public statement from Epik clarifying why they are holding people's money and will not pay it back for several weeks.
But, oddly, the Masterbucks can be spent in-house, so it is not as if the system is frozen. Can you add money to your Masterbucks balance?