bumping to see if anyone has any ideas

Here's my 2 cents worth: if you don't live in a deed restricted community with the Nazi lawn police looking over your shoulder, don't worry about it. People used to rave about our lawn in our previous neighborhood and we use to laugh behind their backs because it was full of weeds, we just kept it fertilized, watered and mowed and it was beautiful. We live in a rural area now surrounded by woods so no-one here cares what your lawn looks like or if you even have one. They are farmers and ranchers who couldn't care less about lawns, landscaping, etc. They are too busy trying to feed their livestock or tend their farms. But there is a grass that grows here in the outlying areas of our property that to me, would be the optimum turf to develop for lawns. I don't know what it is, and I need to take a sample to the extension office to identify it. But it is low to the ground, would never need to be mowed, needs no fertilizer, no watering, no chemicals - what could be better for the environment than that? It's not thick and lush like St. Augustine but who knows what it would look like if it was pampered even half as much? I just think we spend too much money, energy and resources on what we think is needed for lawns. Back in the old days, the only people who had lush lawns were the uber-wealthy who had servants to manicure and tend the lawns. Even then they would have flocks of sheep to keep the grass down.

" I live near the PA/MD boarder, is there any chance I could get some grass seed to take this time of year? " It's highly unlikely. While we're going into a temporary "historic cold snap" of 70 or so, June's about to descend on us. Wait until August 15 or August 23 to seed. While I do see grass in the mix there, it's hard to say how much. Until you kill the black medic, we're not really going to know what state your lawn is in. Probably not very good, but it's not possible to begin improving it unless you start somewhere.

Don't do that unless you have a soil test which shows your soil is short of boron. Boron is an essential micronutrient, but it has a fragile limit. Up to a point, it's good. Just beyond that point it becomes a soil sterilizer where nothing grows. The weed company should at least be able to ID the weed. If they can't then no wonder they can't get rid of it. I would consider (strongly) getting rid of a weed control company that cannot ID a weed while looking right at it. St Augustine is a very salt tolerant grass. Many grasses and grassy weeds, including crabgrass and dallisgrass, can be killed with baking soda. St Augustine seems to survive baking soda. The method of application is very specific to make it work. You can try this and see if it works. Mix some shampoo and some molasses (1 TBSP each) into a pint of water. Put some baking soda into a sock. Spray the weeds with the soapy water. You should not see water beading up on the weed blades. If the water beads up, then use more soap and spray again. Next, while the grass is wet, hold the sock close over the weeds and squeeze the sock. A very fine dust of baking soda will drift out and land on the wet weeds. DO NOT inhale the dust or get it in your eyes. It is very uncomfortable. If there is a slight breeze, you should be upwind of the weeds. It's easy to completely coat the plants with white baking soda. I don't think you need nearly that much. I'm not certain why this works but I have a working theory. Baking soda is a non selective fungicide. Many plants have a protective layer of a fungus which keeps things off and makes the plant uninteresting for predators. It also results in hydrophobia (water beading up on the plant). The purpose of the shampoo and molasses is to make the dust stick to the weed. With the dust stuck to the blades, it can go to work as a fungicide and attack the plant. It should die in a few hours. Surfactants are often called "stickers" in the ag business, because they make a product stick to the plant. But if the sticker dries first, it won't stick, so you're going to be juggling the sticker and the sock. The sock works like a very very fine sieve. Squeezing it contains the baking soda and lets some out without dumping a load of baking soda all at once. Too much baking soda on the soil is not a good thing either. So the baking soda dust sticks to the wet plant, kills the protective fungal layer, then the excessive sodium directly on the plant kills the plant. Here is an illustration of the results. It looks pretty bad, but I think it was mostly crabgrass in the area.