Gasoline will not "eat" any seals in a diesel engine; however, the alcohol that is commonly added to gasoline at about 10% will. Nonetheless, if gasoline content in a waste oil blend is at or below 30%, then all of the seals ever used in a diesel engine will not be affected by the alcohol in modern gasoline blends.
There is a second problem with WMO. It can be a saturated colloid with soot from blow-by, which is very hard to remove, because the particle size in a colloid is so small that they will pass right through the smallest pores of any filter. However, centrifuges have been shown to be affective in removing the sub-micron particles.
There; however, is a 3rd problem with WMO. It can have a high dissolved solids content. These dissolved solids can lead to coking and increased engine wear. The dissolved solids cannot be removed with either a filter or a centrifuge. The only way to remove dissolved solids from a solution is through distillation.