You can technically use an iframe to show the Maximo UI but the user will need to login with their credentials to the Maximo system to do it. If they're not using the Maximo application directly, my assumption is these aren't Maximo users so Michael's suggestion of using the REST API tends to be a better experience for the user. This way the UI can be consistent with the rest of your application and you send the necessary changes to Maximo.
I will caution you though that anyone using your application that can update records will need to have Maximo entitlements. Updating a WO requires licensing in Maximo and we have explicit terms about not circumventing licensing via technical means (https://www.ibm.com/support/pages/licensing-information-and-usage-restrictions) which would apply with an integration.
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Steven Shull
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