It's at least definitely possible for a player to be +EBG yet -EV, the edge case is simple. Suppose the casino bets 100% of its bankroll on each bet, then even though it may have +EV, at some point it's going to lose. So the player will have, with probability one, gained money and hence is at +EBG - though he may require a deep bankroll.
Yes, that's the angry whale with tons of money scenario with over aggressive kelly criterion applied. It was present in Bustabit for a big stretch there all while devans and RHavar profited in excess of a million dollars.
The thing is though that these models assume that there are no investments or divestments in between.
Because the whale is betting at a negative house edge, there should be opportunities for you, as an investor, to pull the rug and divest (not to be confused with deleveraging onsite/offsite) your earnings with profit. This then means that you're not investing anymore, but gambling at a positive house edge.
If, however, you keep your money locked in the investment forever, you make zero at 0EBG and lose it all at -EBG. This is one of the reasons that the predatory system which punishes investors for divesting is just plain wrong.
While taking commission, devans makes his highest profit when the bankroll is its highest; the higher the bankroll, the higher the max profit and amount of wagering can be. That's why it is dishonest and shameful to keep soliciting for a bigger bankroll and to try and pitch Bustabit as a stable investment (lie) with only positive expected bankroll growth (lie) at 1x kelly (lie).
By far, the easiest solution was to cap max profit per game/round at 1% (or 0.75% with commission) with no dilution. You'd think they'd figure it out by now. The excuse that it was to protect the players is absolute bullshit. It's a 1% house edge game strictly against the house with no bonuses at all.