A jog off topic but relevant for missed flight issues.
You might find this older topic interesting. It highlights the pitfalls of DIY a complex trip and buying individual tickets for each leg to save money.
How insurance does or does not cover a missed flight varies. My complimentary card insurance will not pay for a replacement flight if I miss one, but will cover incidental costs of meals and accommodations for delays beyond 6 hours, and additional travel costs incurred to get to an event on time if the causation is outside one’s control with exceptions being for terrorism or financial collapse of a supplier.
As for the ticketing issue
