Shocking service and inferior quality products

We ordered R21500.00 of Saligna decking wood which was delivered 8th December . We sealed the wood with a sealer and topcoat before laying it on our deck .Once the wood was layed we sealed with a few more coats of Woodoc . We went away first week Jan 2020 and when we got back we saw the wood was getting black spots all over it .Then we contacted woodoc and tiger timbers .The wood then started to crack all over and make dark marks .Woodoc blamed the wood that it wasn't air dried properly and TIGER TIMBERS blamed Woodoc saying paint is inferior .Eventually Tiger Timbers offered to replace wood that was cracked .Mike from Tiger Timbers ***) has been promising to do this since before lock down .We have sent numerous emails and phone and they choosing to not honor their side as they ignore our calls and emails .Woodoc also sent us a report from a independent saw mill saying wood could not have been air dried properly .Its shocking that neither company will take responsibility in this matter .It has taken me a year to save for this wood and i want this matter RESOLVED !!!!!!!!! or my money refunded