SERIN2 RoboteQ_RX, RoboteQ_Baud, 15 ,RoboteQ_timeout2,[WAIT("88"), hex2 Encoder1(0)]

... read other bytes here, don't seem to have as many issues with these, they are called with "*89", "*8A", and "*8B", so I only wait for the last digit, the 88 is hard since its two of the same, sometime I suspect I only get on, other times I get both 8s.
Maybe try a longer period before the timeout, and or use two waits. wait for the first 8 then wait for the second 8.