If you want to use Electrum instead of BitGo, then you would be better off generating a new Electrum wallet from scratch and sending your funds from BitGo to it. Having a 2-of-3 multisig wallet in Electrum where you hold 2 of the keys will only cause headaches down the line. Better to just have a standard wallet and send all your coins to it.

If you've lost access to your BitGo account, then try going through their recovery procedures - https://app.bitgo.com/login/forgot-password. They also have a wallet recovery wizard here (https://github.com/BitGo/wallet-recovery-wizard) which would help you recover your wallet so you could then send the coins elsewhere.

Are you sure the keys you are holding are correct? Your "active" private key and back up key, and the public key which corresponds to the private key which BitGo hold on your behalf? This reddit post says the the keys BitGo emails you to store are encrypted with your wallet password. Is this the case with your keys?

Wait, so you have two seeds and two public keys? You said in your initial post you had two seeds and one public key? The seeds are both 12 words long? They are BIP39 seeds, and you are selecting the "BIP39" option when importing them to to Electrum? What letters does the public key (or keys) begin with? "xpub", "Ypub", or "Zpub"?

Does your BitGo address begin with the character "1", "3", or "bc1"? What about the incorrect address you generate in Electrum?

No, it won't. The different address types are totally separate. Any balances on one won't show up on the other.

If you have an xpub, you will only be able to generate legacy multi-sig addresses in Electrum. If the BitGo wallet is showing you a "bc1" address, then you need a Zpub from BitGo to generate that address in Electrum.

different way is https://casa.github.io/xpub-converter/ or here converting xpub to the p2wpkh-p2sh format: https://github.com/AbdussamadA/electrum-convert-key

It's not going to be as easy as that, unfortunately. The xpub public key you have from BitGo will be the public key for the specific derivation path that they use. If you turn it in to the Zpub, then you will end up with the Zpub specific for the same derivation path. There's also no guarantee that the Zpub equivalent of the xpub you have is the correct one for your addresses.

Having a look through their documentation did reveal the following:

Given that, you could try creating a multisig wallet in Electrum, on the page that follows after entering both seeds select "native segwit multisig" and then change the suggested derivation path to m/0/0, and for the third key enter the Zpub you obtained from the tool you linked.

If that doesn't work (and I'm not hopeful it will), then you'll need to contact BitGo.

I read your address begin bc1, your derivation path is wrong as native format, true is m/84'/0'/0'/0 not 48

m/48'/0'/0'/2' is the correct default derivation path for multi-sig native segwit in Electrum. m/84'/0'/0' is for standard (non-multi-sig) wallets.

That response is very unhelpful. At this point I would just use their wallet recovery tool and sweep all the funds to a normal Electrum wallet.