FetchXML report from three different entities

I am trying to write a report about Accounts showing all contacts with this Account as parentcustomerid and all positions with this Account. This is for use with Dynamic 365.

I need to go from Accounts with show all Contacts for this  Account and show all Positions for this  Account.

I wrote the following query.

<fetch version="1.0" output-format="xml-platform" mapping="logical" distinct="false">
<entity name="account">
<attribute name="name" />
<attribute name="primarycontactid" />
<attribute name="telephone1" />
<attribute name="altai_memberid" />
<attribute name="websiteurl" />
<attribute name="emailaddress1" />
<attribute name="accountid" />
<attribute name="address1_composite" />
<attribute name="fax" />
<order attribute="name" descending="false" />
<filter type="and">
<condition attribute="psats_municipalitytype" operator="eq" value="340970000" />
</filter>
<link-entity name="contact" from="parentcustomerid" to="accountid" visible="false" link-type="outer" alias="Contact">
<attribute name="psats_suffix" />
<attribute name="middlename" />
<attribute name="altai_memberid" />
<attribute name="lastname" />
<attribute name="firstname" />
<attribute name="emailaddress1" />
<attribute name="parentcustomerid" />
</link-entity>
<link-entity name="altai_mbr_position" from="altai_accountid" to="accountid" visible="false" link-type="outer" alias="Positions">
<attribute name="altai_startdate" />
<attribute name="altai_mbr_programid" />
<attribute name="altai_contactid" />
<attribute name="altai_accountid" />
<attribute name="altai_enddate" />
<attribute name="altai_positiontitleid" />
<attribute name="altai_mbr_positionid" />
<attribute name="psats_termexpires" />
<attribute name="statuscode" />
<attribute name="statecode" />
<attribute name="altai_positiongroupid" />
<order attribute="altai_accountid" descending="false" />
<filter type="and">
<condition attribute="statecode" operator="eq" value="0" />
<condition attribute="statuscode" operator="eq" value="1" />
</filter>
</link-entity>
<link-entity name="account" from="accountid" to="altai_accountid" alias="ac">
<filter type="and">
<condition attribute="psats_municipalitytype" operator="eq" value="340970000" />
</filter>
</link-entity>
</entity>
</fetch>

When I place this in visual Studio I receive the following error.

The tablix has a detail member with inner members. Detail members can only contain static inner members.