This looks correct to me, so long as there are no existing issues with record type assignment.
Marketo has a few help articles around the Delete Lead in SFDC and Delete Lead in Marketo for your reference:
https://community.marketo.com/MarketoArticle?id=kA050000000LAB1CAO&refURL=http%3A%2F%2Fcommunity.mar...
https://community.marketo.com/MarketoArticle?id=kA050000000L3hzCAC&refURL=http%3A%2F%2Fcommunity.mar...