Second party audits

It is the Remote Site for both our SG Company (Singapore) and JP Company (Japan).
Do we need to conduct 1 internal audit by SG and 1 Internal Audit by JP?
Or can we send 1 representative/auditor from TTS or TMC to conduct internal audit in our remote site (US)?
And can the Audit result/documents can be used by both SG and JP?
By the way, our CB for SG Company is SGS while CB in JP is DNV GL Japan, but Certification standards are both IATF16949:2016.
Can we, JP and SG share 1 audit result even we have different CB?
Our main headquarters/company is in Japan, we have manufacturing Company in different places like Singapore, Thailand and Malaysia. Our remote site were under Japan and Singapore Company

Answer:
As long as the internal audit to the Remote Site is made by a competent auditor that satisfies the requirements of both SG and JP companies, and follow the approved procedures, one auditor can make the audit and send the report to both companies. Each company should analyze the report and evaluate the need for any request of improvement or correction. There is no problem of sharing one audit result with different companies even with different Certification Bodies.

By the way, when ISO 9001 was developed in 1987 the initial purpose was not to be used by third parties (certification bodies). ISO 9001 was developed to be used by clients to audit suppliers. Then clients, multinationals, promoted the idea of certification because audit costs would be paid by suppliers. What SG and JP companies want to do is the same thing, using an independent auditor to do the job in their name.
The following material will provide you information about second par audits:
- ISO 9001 – First-, Second- & Third-Party Audits, what are the differences? - https://advisera.com/9001academy/blog/2015/02/24/first-second-third-party-audits-differences/
- free online training ISO 9001:2015 Foundations Course – https://advisera.com/training/iso-9001-foundations-course/
- book - Discover ISO 9001:2015 Through Practical Examples - https://advisera.com/books/discover-iso-9001-2015-through-practical-examples/