cfpdfform doesn't generate file - java.lang.NoClassDefFoundError

Since upgrading from CF11 to CF2021, the <cfpdfform> tag no longer works - that said, not sure if the upgrade is the issue or not.

In the past (on CF11), we’ve successfully generated a pdf file with the code:

<cfpdfform source="Avery45008CopierMailingLabels_HBD.pdf"
destination="E:\HBD_DEV\files\DestiAvery.pdf"
action="populate"
overwrite="true"
overwriteData="yes"/>

No file is generated, nor is there an error message displayed in the browser (see exception log below).

I've also used the following code, as suggested by CFSupport via StackOverflow, which results in the same error:
<cfpdfform source="Avery45008CopierMailingLabels_HBD.pdf"
destination="E:\HBD_DEV\files\DestiAvery.pdf"
action="populate"
fdf="true" />

Coldfusion 2021: Update 5
Our JAVA version is: jdk-11.0.17

We've also deleted all files in the cfusion/bin/felix-cache and cfusion/wwwroot/WEB-INF/cfclasses folders. No love.

Looking in the exception log, we find:

(the culkprit appears to be "java.lang.NoClassDefFoundError: coldfusion/tagext/document/DocumentSectionTag
at coldfusion.tagext.pdf.PDFFormTag.doStartTag(PDFFormTag.java:240)")

Exception log:
"Error","ajp-nio-127.0.0.1-8020-exec-1","11/29/22","10:47:46","HBD_DEV","coldfusion/tagext/document/DocumentSectionTag The specific sequence of files included or processed is: E:\web-sites\Production Sites\medical_neuroscience\hbd_DEV\admin\reports\ajax_MailLetter_Results.cfm, line: 77 "
java.lang.NoClassDefFoundError: coldfusion/tagext/document/DocumentSectionTag
at coldfusion.tagext.pdf.PDFFormTag.doStartTag(PDFFormTag.java:240)
at cfINCLUDE_CreateMailingLabels2ecfm1982419870.runPage(E:\web-sites\Production Sites\medical_neuroscience\hbd_dev\admin\reports\INCLUDE_CreateMailingLabels.cfm:77)
at coldfusion.runtime.CfJspPage.invoke(CfJspPage.java:257)
at coldfusion.tagext.lang.IncludeTag.handlePageInvoke(IncludeTag.java:749)
at coldfusion.tagext.lang.IncludeTag.doStartTag(IncludeTag.java:578)
at coldfusion.runtime.CfJspPage._emptyTcfTag(CfJspPage.java:5201)
at cfajax_MailLetter_Results2ecfm1408795013.runPage(E:\web-sites\Production Sites\medical_neuroscience\hbd_DEV\admin\reports\ajax_MailLetter_Results.cfm:54)
at coldfusion.runtime.CfJspPage.invoke(CfJspPage.java:257)
at coldfusion.tagext.lang.IncludeTag.handlePageInvoke(IncludeTag.java:749)
at coldfusion.tagext.lang.IncludeTag.doStartTag(IncludeTag.java:578)
at coldfusion.filter.CfincludeFilter.invoke(CfincludeFilter.java:65)
at coldfusion.filter.ApplicationFilter.invoke(ApplicationFilter.java:613)
at coldfusion.filter.RequestMonitorFilter.invoke(RequestMonitorFilter.java:43)
at coldfusion.filter.MonitoringFilter.invoke(MonitoringFilter.java:40)
at coldfusion.filter.PathFilter.invoke(PathFilter.java:162)
at coldfusion.filter.IpFilter.invoke(IpFilter.java:45)
at coldfusion.filter.ExceptionFilter.invoke(ExceptionFilter.java:97)
at coldfusion.filter.ClientScopePersistenceFilter.invoke(ClientScopePersistenceFilter.java:28)
at coldfusion.filter.BrowserFilter.invoke(BrowserFilter.java:38)
at coldfusion.filter.NoCacheFilter.invoke(NoCacheFilter.java:60)
at coldfusion.filter.GlobalsFilter.invoke(GlobalsFilter.java:38)
at coldfusion.filter.DatasourceFilter.invoke(DatasourceFilter.java:22)
at coldfusion.filter.CachingFilter.invoke(CachingFilter.java:62)
at coldfusion.filter.RequestThrottleFilter.invoke(RequestThrottleFilter.java:151)
at coldfusion.CfmServlet.service(CfmServlet.java:231)
at coldfusion.bootstrap.BootstrapServlet.service(BootstrapServlet.java:311)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
at coldfusion.monitor.event.MonitoringServletFilter.doFilter(MonitoringServletFilter.java:46)
at coldfusion.bootstrap.BootstrapFilter.doFilter(BootstrapFilter.java:47)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:197)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:377)
at org.apache.coyote.ajp.AjpProcessor.service(AjpProcessor.java:463)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:889)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1743)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191)
at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.base/java.lang.Thread.run(Thread.java:834)