CALLING ALL LAUNDRY WIZARDS!!

A few weekends ago, my darling husband was assisting his father with a project. During the course of said project, my husband proceeded to soak himself in hydraulic oil. He tells me it's the same as vegetable oil. I looked at the said shirt and said to myself "Well that will never come out." After returning home from Gramma and Grampa's, said shirt was tossed into the laundry. Keep in mind that Dan has had this shirt as long as I have known him (1996) and the shirt wasn't new then. It was black (even better for showing oil stains!) but over the years has developed a dusty hue. I have tried numerous times to replace said shirt, but alas, "The new ones just don't fit right." Maybe if they were old enough to graduate high school, they would be a little more comfortable! He also has a lovely matching blue one. ANYWAY, I digress. After being washed, dried, lovingly folded and put back in the drawer (with remaining oil stains), my darling husband came to me in a huff and said "They are still there" (picture bottom lip puffed out). Of course he was pointing out that the oil stains had not magically disappeared in our genie machine. I proceeded to tell him that they most likely would never come out and that I didn't put them there. He told me "You didn't even try." I'll admit I didn't. IT'S OIL!! So, last night after I had washed it once again and then let it hang dry to see if they miraculously disappeared (they didn't) I had to tell him they were still there. Please imagine the face and body language of a 4 year old boy who had just pulled the head off of his favorite G.I. Joe. Knowing full well that he caused the demise, but loving it just the same. I caved. I told him that I would try again. The shirt is currently soaking in the kitchen sink in Dawn (it puts grease on the run...right?!) If this doesn't work, I am out of ideas. I wouldn't be too crushed if it didn't work, but I unfortunately know that my darling husband would begin to think of the oil stains as mere details to his wondrous shirt and continue to wear it anyway. If you have any suggestions to remove these oil stains, please do share! Otherwise, that guy at the grocery store that looks like he ran through the oil sprinkler, Yeah, that's my husband!