I’m sorry to hear of their fight
Do you mean you had them together in a 1x2 c&c? If so, then you absolutely did the right thing by trying to increase their cage size. It would not have been appropriate to leave them in a 1x2 c&c as it does not meet even the minimum welfare standards. The smallest cage two piggies should be kept in for welfare requirements is 8 square feet but two boars actually need 12 square feet. A 1x2 c&c only comes to 2 square feet
Even a single piggy need 8sq ft minimum so a 1x2 each would still not have been big enough for them even if they lived separately previously
You say they had a fight doing an introduction. So, have they not lived together in the same cage before?
Did you introduce them properly on neutral territory?
If they have not lived together before and you were trying to bond them on neutral territory, then the fight has occurred because they are not compatible. Two piggies who are not compatible will not be able to live together.
A 2x5 is the right size for two boars (a 2x4 is usually still even too small for two boars) to live in but changing the cage size of a pair who were already living together constitutes a change in environment and territories. Such a change can sometimes cause underlying issues to come to the surface and cause piggies to fall out. Any time a cage size is changed it’s advised to be careful and ensure that old bedding is used so that it still smells of them as that can sometimes help them feel more secure.
Equally, you have pigloo hides which only have one door in them. Those hides are not recommended as there is no way out if one piggy is inside it and the other traps them inside. All hides should always have two exits.
I’m afraid though that now a blood drawing fight has occurred it’s unlikely they will be able to share a cage again and will always need to be kept in a divided cage.
If they do need to be kept permanently apart, then you would need to extend the cage again as currently each piggy in a divided cage does not have enough space. The minimum size for a single piggy is a 2x3 cage each.
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