If your database, option values, username or password contain characters used to delineate DSN parts, you can escape them via URI hex encodings:
: = %3a / = %2f @ = %40
+ = %2b ( = %28 ) = %29
? = %3f = = %3d & = %26
In your case you have to use
MAAS_DBPASS='Verygood1%40lab'
and you should be good to go