Both sets of parents hijack wedding plans, what to do?

WIBTA for eloping when the wedding is this weekend?

My girlfriend and I had planned to get married on Saturday. We wrapped up all our planning around Halloween, all that was left was to ring some time this week and make sure everything was running smoothly.

She called the venue and the person she spoke to asked her to confirm some changes she'd apparently made. My girlfriend had no clue what he was talking about, and he reminded her of all the changes that had been put in recently. We had not approved any of these changes. We were able to get some of it put back the way it was but there are some things that we couldn't change back at such short notice.

The venue forwarded us the emails asking for the changes so we could look over them. Our communication was being done via an email account we created solely for wedding stuff, and the email address which asked for the changes is the exact same address, except 2 letters are switched round. The venue is very apologetic for not calling us directly but can only fix so much of it at this stage.

We think we know what happened. The whole time we were planning the wedding we got pushback from both sets of parents, and the stuff they had the biggest issues with have all been changed. I'm willing to bet that all of this was related to at least one of our respective parents. We don't know anyone who would want to fuck with us or the wedding this badly except our parents, who got pissy when we told them they couldn't financially contribute to the wedding because they were trying to trade their money for whatever wedding stuff they wanted.

Right now the stuff that we wanted that is still in this wedding is my suit, the venue and the DJ. My girlfriend has gone to pick up her dress and she's not heard from the shop so we're assuming that hasn't changed. I'm calling round everyone and it looks like the menu has been changed, as has the guest list and the cake. We paid for the wedding we'd planned and it looks like any additional costs from the changes (such as the extra people) were paid for by someone else, but they wouldn't give me any of the card info for legal reasons.

We probably won't be speaking to our parents again after this, unless one of them owns up in which case we'll just stop speaking to that one, but this feels like a joint effort as it's dealt with both sets of parent's complaints.

Before my girlfriend left to get the dress she gave me permission to post this as we are seriously considering eloping. We have the marriage certificate here, the honeymoon is unaltered and exactly what we wanted, and there's a few appointments we could make between now and Saturday at the town hall to get the certificate legally signed/filed.

However, we now have around 200 people attending this wedding in 3 days (our original guest list was about 100 including families and plus ones). People have booked hotels, planes, trains, and are coming from other countries to be here. None of these people have done anything to us and would be getting caught in the crossfire if we were to elope instead.

Would we be the arseholes?

Update: I posted in the group chat I have with all 4 parents that someone has been screwing with the wedding, we've found the email they used and we'd be tracking the IP address to a device and location (this was all absolute bullshit, we don't even know how to find an IP address). As soon as I said we'd be tracking the email they all started pointing fingers and accusing each other. It looks like all 4 of them were in on it together. Still not sure what we're doing about the wedding but all 4 parents are uninvited.

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We're thinking that we might elope for the ceremony and then have the reception as planned (it's all the same party/venue and we won't get money back) because of the number of people who are coming from all over the place.

Edited to show original post. Link left so we can get at the comments over there