EVCS went through a growth spurt of sorts (perhaps through acquisitions?) but that progress has slowed considerably as of late.
As for the temporary holds, unfortunately that is becoming typical across the board (in any kind of transaction). I get temporary charges of $0.00 and $1.00 all the time now just when entering my credit card info for an online transaction. Obviously in your case they are trying to ensure they can capture at least $20 if they need to, which is reasonable, but the fact that they need to repeat it after a failure sucks. Fortunately I suspect they immediately cancel the charge after an unsuccessful session, but what I would be wary of are sites that have a connection fee, so you would be charged something like a $5 connection fee and then per kWh or per minute after that. What happens if the session fails prematurely then?