Have just re-read the thread in detail and I see that prior to the course you did evening seasonal work OP. How come you managed financially ok then and got by, whereas now you're suddenly in danger of losing the house? Presumably with seasonal work, you weren't even entitled to maternity pay? Anyway, even if this is the only option, presumably you could pick that work up again when the season starts.
You clearly feel people are criticising you and aren't happy that you're not getting the response you wanted. But people have given you excellent, practical advice on here and explained that you are highly unlikely to walk into a permanent teaching post where you'll be able to afford transport and childcare upfront, particularly when you live in a rural area. Everyone I know who's got a teaching post within the last few years has had to start from volunteering, working a few years as a classroom assistant , doing supply etc- and most of these are people who have experience and have had a few years out of work at home. You've not taught since qualifying so how are you possibly going to compete with others, including the new cohort who will have graduated as teachers since you did, most of whom will be prepared to move anywhere for teaching work.
I still think the answer is to relocate if you are serious about it as a career because living rurally with fewer accessible schools and childcare provision will limit you from the get go. In your position, making the massive decision to retrain, I would have factored that into the initial discussion with your dp. It would have been sensible to make a broader plan about how to maximise your employability rather than just going and doing a years post grad training and assuming you'd fall into a job on your doorstep. Did you do your research prior to doing the PGCE about employment rates among history teachers; it's not too hard to access information about how many history posts for newly qualified teachers come up on average within striking distance of where you live
Anyway if you're not interested in the broader advice on here, and just want a response to your OP, then I'd say YABU. You are in dire financial straits, at risk of losing your house and are wanting to spend £80 of household income on a course which realistically is not going to be make or break. The course leader may well be excellent, but as everyone says, you need more than excellent applications and interview technique. Experience in schools is going to be a bigger factor because that's a better indicator of how good you are in the classroom. And tbh you can find other ways to sharpen up interview technique anyway. If you establish contact with a local school, one of the senior teachers Or head of history would probably be happy to give you interview practice.
The final point is that friends of mine (and my SIL who teaches) have had to adopt a far more 'can do' approach to working than you seem to have. They've often had to go out of pocket paying childcare upfront before getting supply work. They've had to be prepared to travel for supply, sometimes spending out a lot on petrol before their pay arrives. My SIL had to pay well over the odds for childcare when her kids were small because she needed a childminder from 7 am to get to work by 7.45 which is very normal in teaching. I think if there are so many barriers to you adopting this approach right now, then maybe you just need to wait until your youngest qualifies for some free hours nursery, invest in a cheap runaround car then, and try your hand at supply. And then of course once your youngest is in school you will have far less childcare expenses. But even for supply you will need before and after school care for your children so I would start planning for that now
Good luck