Mortgage broker messed up with my application - do they have to reimburse me?

[BroomstickBicycle]

My mortgage broker found me a suitable deal but failed to check whether this deal was still available when he submitted the application 3 days later.
Roll on 4 weeks later and I receive my mortgage offer only to discover that the fee and ERC has doubled, making the deal no longer suitable. Broker has admitted their mistake but is now pushing me to another deal with the same provider saying it's cheaper because they can turn it around quickly, thereby avoiding me having to pay over the odds on my current SVR while we apply to another provider. Which would make sense except that I'm only in this situation because they fucked up the original mortgage application. If they had checked the deal when they submitted the application I'd have gone for the other provider. I feel they should cover the extra I have to pay on SVR while I apply for another mortgage given they made the mistake (we are talking about £1.5k).

Am I likely to get them to pay this?

Your broker should reassess all deal available TODAY, and place you with the most appropriate provider. I.e as close to your original deal as possible.

I find it hard to see that big a change in the offerings from the mortgage company, very little movement on rates and offerings at present?

Maybe search the provider website and see what deals they can access

google "name of provider + intermediary mortgage products"

Getting back the £1,500 would be a challenge, you may be able to offset this with their fee, and /or a portion of the proc fee paid back

Thanks for replying. The broker's rates are competitive compared to the published rates.
I've not given them any money yet. The valuation I had for the original application was free.