Does a marriage by custom with a first spouse becomes invalid by virtue of a marriage by ordinance with a second spouse?

No. The purported second marriage is rather not valid if it is a marriage under ordinance. The second marriage can only be valid if it is contracted under customary law or Mohammedan Law, both of which a polygamous in nature. Such a second marriage cannot therefore be converted into an ordinance marriage until the first marriage is dissolved.

No. A marriage by custom is not invalidated by a second marriage under the ordinance with a different spouse. This is because customary marriages vastly allows polygamy and does not prohibit contracting futher union by a spouse with another party under any other statute