Hi Heidi:
I can't explain the wording of the message, but I have a suspicion of what may be the cause for the failed import:
When you create the fields in Salesforce, they come into Marketo as "Integer" (number) fields. However, in order to use them for scoring, Marketo requires them to be switched to "Scoring" fields.
Please go into your Marketo Admin, select Field Management, and search for these fields - What does the "Type" say?
If it says "Integer" and you are working with a Marketo Consultant, please ask him to change the field types to "Score". Otherwise, please submit a Support Request.
Then try the import again.
Hope this helps!