For those of you questioning the x5 wagering rule, its purpose has been covered in some detail already in the thread RE their latest casino Slotty Vegas:
Some of you may not even be aware that Slotty Vegas is owned by Betat casino.
Igor's post #42 reflects recent changes to the wagering rule at Slotty Vegas, made based on players concerns.
You can read it here:
https://www.casinomeister.com/forums/threads/betat-presents-slotty-vegas.63282/
I don't know if Betat plan to amend their term at any point in line with the amendment made to the same term at Slotty Vegas, but you can check with Igor if you're interested to find out.
As has been stated before me, although not with absolute certainty by at least one poster, the x5 wagering term was indeed designed to help minimise money laundering efforts. It's not the first time I have seen this exact term at an accredited casino either, nor do I personally have an issue with it. The casino looks collectively at the playing style of its customers, and doesn't make a decision based on just one or 2 things.
It is no fluke that Betat have a good reputation, and have achieved accredited status here. If the casino is indeed holding the OP's withdrawal request based on the x5 wagering rule, then I suspect there is more at play here.
PS: There's plenty of interesting reading in the Slotty Vegas thread, and I encourage anyone interested in this group to read right through it from start to finish.