blank names are not banned
dot in the chat - probably coincidence
i never heard of such way to lagging the server
are they douches? yes! punish them (damage all their bases and troll them without breaking the TOS)
but are they cheaters? no evidence of that for now, some screenshots and videos would be helpful
The main question how good your base was hidden?
and how quickly they manage to locate it?
and probably, there no hidden spots left (without glitching) at EL at all so…