I have enough social anxiety to be unable to impose myself in this way, sadly. lmao
I am very sorry. When you can, please see a vet. You do not need to see them three times.; they can give you the ivermectin or selamectin based product and tell you at which interval you need to repeat the treatment twice. While good quality ivermectin is not quite cheap, it is also by far not the most expensive treatment.
Here is more US based information on ivermectin; google to see whether it is available online in your country at the right strength.
Guinea Lynx :: Lice
The problem with ordering cheaply online is that you do not have control over whether you get a cheap fake or the proper product, which is why ordering from a reputable vet provider is not quite as cheap but it gives you more protection.
In the meantime, please put your piggies together by introducing them on neutral ground. Our step-by-step bonding guide will help you with that. You cannot just stick a piggy in another piggy's territory.
Here is the link:
Bonding and Interaction: Illustrated social behaviours and bonding dynamics
The need for company is not just overwhelming at this age, lack of it is also a major stress factor that is contributing to your baby not being able to get on top of the lice.
They are both still quite young with their immune system still under construction, which is one reason why pet shop or breeder babies are so vulnerable to skin parasites, fungal skin and respiratory infections - these common problems have all one thing in common: they are contagious and they are all opportunistic issues that generally hit when the immune system is not stong or lowered by young and old age, pregnancy, illness or major stress.
What you CAN do until you have the necessary money is to concentrate on companionship and a good diet. Diet is key for building up a long term strong immune system that is a much stronger and better defence against skin parasites. It also can add 1-2 years to your piggy's life span. Unlimited hay and fresh growing (dog pee free) grass is the most most important food; it is what guinea pigs have evolved on - both their digestive system and the teeth, which are very fast growing to balance against the silica in grass and hay. Fresh grass is rich in vitamin C and good quality hay also contains it; they are the reason why guinea pigs never had the need to make their own vitamin C. Green vegetables and fresh herbs replace other plants guinea pigs would eat to supplement their grass based diet for trace elements. But they need comparatively little of them. 1 tablespoon max. of pellets (please no dry mix if possible) per piggy per day is enough; pellets are the part of the diet that can be left out if you can supplement fresh veg with some dried forage.
A good diet alone cannot make your lice disappear because it takes several weeks before it really starts making a difference, but it can help your piggies to fend them off and it can in the long term help them to not get another outbreak again and to be overall much healthier.
Here is more very detailed information on a good diet. That is in the longer term the best weapon against illness:
Long Term Balanced General And Special Needs Guinea Pig Diets
Because of the time difference between you and our forum, which is based in the Untied Kingdowm, I would strongly recommend that you save these information and practical help links here in case you need some quick information when we are are not around. We have one of the most extensive information collections on guinea pigs that you can find:
Getting Started - New Owners' Most Helpful Guides
Emergency Resources and Critical Illness Care - Contents list and subforum link
I hope that this helps you? Please take the time to look at the green links in my posts.
My fear is exactly that, lice getting resistant. I'm not going back in this petshop.