Sean, I am not personally familiar with the machines you bought, but there are common elements to getting good shots. How recently the beans have been roasted is not your biggest concern here, or even a concern. It sounds to me that you are proceeding properly, but maybe you will have quicker success if you reverse your course and start from a course grind, and work your way finer. I have often read that 30lbs is the ideal tamp pressure. For many people, specially men, that is a lighter tamp than you would think. I actually prefer a heavier tamp much of the time, and grind accordingly. That is the point. WLL videos are really good for information. Probably some of the best. But, that said, you are still finding your own personal route to the perfect espresso shot, so don't get too caught up in the numbers on the machines working out according to what is recommended in the manual or the videos. There are many variable, including water quality and condition. For example, everytime I move, I install an Easy Water system because it improves my coffee, showers, and my shaving a lot. It takes 6 months or more to become fully functional and I have to make several adjustments over that period. You have to consider that you have an unseen variable effecting the outcome, and you have to experiment to compensate.
The one variable that can be difficult to overcome are beans that are too oily. Whenever you buy beans from WLL, you can call and talk to someone about the suitability of the bean you are interested in, to the machines you own. In the past, before I finally convinced myself that it's worth paying for good beans, I purchased from Costco, Sams Club, and Trader Joes. Costco and Sams Clubs beans are very often oily. I feel as if the name brand manufacturers know this and are dumping unsatisactory product there, because of the lower prices. My personal opinion! Trader Joe beans, specially the French Roast, can sometimes be too oily as well (because of the darkness of the roast). You will find most Lavazza from WLL to be fine, but there is a roast (can't remember which) that is oily, and the staff will tell which ones are which. WLL has a vast selection of beans to try, and it's just fantastic working your way through the garden, so to speak. Good luck.