A conclusion about accessibility from a meta-study on ownership is not something that you should be citing. Its not an argument of semantics, when people talk about accessibility of guns they mean how easy it is for a person to get a gun, not if it is in your reach because you already have one in your home. One of the studies cited, I believe number 10, even explains how they quantify the "accessibility" of guns; its not the same as gun ownership.
Furthermore, if you are going to define accessibility as "having access to that firearm", then dont link that 3rd study, as it defines it differently and you shouldn't have linked the first as the studies that it cited focused on gun ownership and not accessibility.
You should at least seek consistency between your definition of accessibility and accessibility as defined by one of your citations, especially in the sort of meta study they conducted. Yes, it is a significant difference because gun ownership and gun accessibility are different in terms of gun control. Gun ownership would relate to who is a victim or perpetrator of a violent crime, gun accessibility would be in relation to the frequency of violent crime.
Maybe read the studies before you link them. Anybody can google and copy a link that looks official. Or make a rebuttal that's more than "nothing you said is valid" because Im pretty sure that citing one study that talks about people living alone then turning around and making a statement about domestic violence is evidence of obvious bias.