The SALT has handled that very badly – I'm so sorry you were blindsided in that way and then left with no sense of what the next steps should be.
There are patterns of language acquisition that are more common in autistic children, so it's possible she saw some of these in your daughter (but if so, she should have explained it!). For example, early words being heavily dominated by numbers/letters/shapes/colours/similar, with few of the common, high utility words most children start with (mama, dada, up, hiya, bye-bye, names of siblings, pets, favourite toys, favourite foods, favourite activities). Another example is words being used almost exclusively used to 'label' rather than communicate, so like naming things she sees, but just for herself, not caring if you hear her or not. Another is gestalt language processing, so learning phrases, sentences, or longer 'chunks' of languages and repeating them fairly exactly, rather than learning individual words and then learning how to put words together in different ways. Do any of those sound like your daughter?
The questionnaire @BunnyRuddington linked to is an additional one that goes into more depth just on social and emotional development, so it is worth looking at in addition to the general Ages and Stages questionnaire. I would also second pushing for a referral for a hearing test (in some places you can self refer, so worth checking if that's true for your area) and for a referral to paediatrics. Best to get on the waiting list as soon as you can, and if you no longer have any concerns by the time they offer you an appointment, you can easily cancel.
If she's in any sort of childcare, it's definitely worth having a chat with them about what they've observed. An experienced childcare professional has seen a lot of two year olds, and can have an excellent sense of what's in the broad range of typical development and when a little extra support might be a good idea.