Could there be a Frequency problem?

Unlikely.

Give us a few clues - what mics and DIs did you use and where were the mics placed in relation to the guitar amps?

Do the drums and vocals sound OK?

Can you post a sample?

When you turn one of the guitars down, does the other one seem to get louder? I'm totally guessing on this but, my guess is that it's the guitars are out of phase with each other. I could be way off base but that's pretty normal for me. I'm just trying to feed the fire.

My guess as to the difference in sound for your electric guitars is the probability that you heard your electric guitar amplifiers from further away than where the microphones were placed on the cabinets? I assume the microphones were probably right up to the front of the cabinets Grill, where you were listening to the cabinets from across the room. Of course they won't have the same sound that way. And so in many ways you may have actually answered your own question and that is, put one microphone up to the cabinets Grill and put another microphone somewhere else in the room. Combine the 2 carefully to provide you with the sound that you seek.

Thinking outside of the speaker box
Ms. Remy Ann David

We close miced the amps with a SM57 Mic. Our producer solved the problem with the guitars when he re mixed it once more. I don’t know how he did it, but everything sounds way better now.

We will probably experiment with more mics next time.

Thanks!