Those in Paraguay most likely won't come. Wes & Rachel came for John & Campbell's wedding, but not Kressant & Mike. And, Mike was apprently just here earlier in the year, so I doubt they'll load up and come again.
They'll get bridesmaids dresses wherever. Martha had a giant wedding party, but the dresses were not matching at all and in varying shades- they all clearly got whatever dress they wanted, wherever they wanted (nothing wrong with that in my opinion). Plus, they made all the bridesmaid dresses for the first three S'Morton weddings as well as Dorothy's - so they sew. Alyssa's wedding was short dresses that I think they got from Target - I seem to recall one of them having an IG story about that. Bridesmaids dresses are not going to cause a problem. Also, since they sew, and off the rack wedding dress where they do alterations is not out of the question. The groom/groomsmen in various Morton weddings have worn less than tuxedos so I don't think there will be an issue with getting them clothed either.
Having the wedding on the compound eliminates any venue issues - the family/friends do all the food, set up, decorating, etc. They have that whole "wedding barn" as it was once named when the S'Mortons were marrying up. Indoor/outdoor venue right at home that they can do with as they wish to make it work. A friend who calls themself a photographer will no doubt take the pictures. Among their circle there are many SAHD's who are "photographers".
Non fundie weddings would be a hard sell in that time frame, but in Morton-ville - they have the venue; they no doubt have decorations up the wazoo lying around from the past weddings they've held - Andrew & Kennedy were married "on the farm" just five years ago and Martha just a year before that, they have an army of friends & family right there to do the work. They can sew. They have never seemed interested in overly fancy, costly attire.
I really don't think the Mortons will have a problem pulling it off.
For as much as I disagree with them and their way of life, they are resourcesful and after the S'Morton marriages, the weddings they've thrown for their kids have been nice events. Not my taste but nice.